CN106654427A - Formation method for lithium ion battery - Google Patents
Formation method for lithium ion battery Download PDFInfo
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- CN106654427A CN106654427A CN201710053448.3A CN201710053448A CN106654427A CN 106654427 A CN106654427 A CN 106654427A CN 201710053448 A CN201710053448 A CN 201710053448A CN 106654427 A CN106654427 A CN 106654427A
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- Prior art keywords
- voltage
- current
- lithium ion
- ion battery
- constant
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
- H01M10/44—Methods for charging or discharging
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
Abstract
The invention provides a formation method for a lithium ion battery. The formation method comprises the following steps of adopting different low currents, performing constant-current charging on a to-be-formed lithium ion battery at different stages to obtain a pre-formed lithium ion battery, and standing; adopting first current, performing constant-current charging until a charging cut-off voltage of the lithium ion battery is achieved, then performing constant-voltage charging for the first time, and standing for the second time; adopting second current, performing constant-current discharging until a discharging cut-off voltage of the lithium ion battery is achieved, and standing for the third time; repeatedly executing the above steps; and finally, adopting a third current, performing constant-current charging to a fourth voltage, and performing constant-voltage charging again. In the formation process of the lithium ion battery, namely the first round of the charging process, pre-formation and main formation steps are performed; and low-voltage trickle formation at different stages is adopted in the SEI membrane forming stage in the front stage, so that co-embedding of solvent Li ions can be effectively prevented, growth time of membrane compact components is increased, the composition and structure are stabilized, and a more compact SEI membrane is formed on the surface of a negative electrode material.
Description
Technical field
The present invention relates to lithium ion battery material technical field, is related to a kind of chemical synthesizing method of lithium ion battery, especially relate to
And a kind of chemical synthesizing method of the lithium ion battery that can form fine and close SEI films.
Background technology
Lithium ion battery is a kind of secondary cell (rechargeable battery), and it relies primarily on lithium ion and moves between a positive electrode and a negative electrode
Move and carry out work.In charge and discharge process, Li+Embedded and deintercalation is come and gone between two electrodes：During charging, Li+From positive pole deintercalation,
Through the embedded negative pole of electrolyte, negative pole is in rich lithium state；It is then contrary during electric discharge.Battery typically adopts the material containing elemental lithium
It is the representative of modern high performance battery as electrode.
Lithium ion battery has that operating voltage is high, specific energy is high, has extended cycle life, lightweight, white electric discharge less, memoryless effect
Should be with cost performance ratio, so in recent years, lithium ion battery is more and more in portable electric appts, electronic vapour
Car, space technology, national defense industry, artificial satellite and Aero-Space etc. it is many-sided it is multi-field illustrate wide application prospect, and
Become the main selecting object of rechargeable type power supply.Therefore lithium ion battery and its associated materials become the research heat of scientific research personnel
Point, while this also puts forward higher requirement to the performance of lithium battery, such as high voltage, high power capacity, high security, good cycle
Etc..
During the manufacture craft of lithium battery, in the case that electrode material determines, chemical synthesizing method is to determine whole battery
The step of performance most critical.Battery formation refers to that the process to the battery primary charging of new production is exactly to encapsulation with small current
The lithium ion battery for completing is charged active material activity, and its purpose is to form one layer of passivation layer in negative terminal surface, with
Protect whole chemical interface.The chemical conversion of lithium battery mainly plays the role of two aspects：One be make in battery active material by means of
Charge for the first time and change into the material with normal electrochemical action；Two is to make electrode be mainly carbon material used as anode surface to be formed
Even effective passivating film, i.e. solid electrolyte interface film (SEI films).Battery formation is generally divided into constant-current charge and constant-voltage charge two
In the stage, generally chemical conversion time control is in 24h or so.
In the technique of Battery formation, the compactness extent of the SEI films that negative terminal surface is formed directly affects the self discharge of battery,
A series of performances such as irreversible capacity loss, cyclicity, forthright again and security.
Therefore, a kind of chemical synthesizing method of lithium ion battery preferably how is found, lithium ion battery is further improved
Chemical property, it has also become one of focus of many line researcher's extensive concerns in field.
The content of the invention
In view of this, the technical problem to be solved in the present invention is to provide a kind of chemical synthesizing method of lithium ion battery, especially
It is a kind of chemical synthesizing method of the lithium ion battery that can form fine and close SEI films, the chemical conversion side of the segmentation discharge and recharge that the present invention is provided
Method, can form the SEI films of densification, so as to improve the combination property of lithium battery.
The invention provides a kind of chemical synthesizing method of lithium ion battery, comprises the following steps：
A) different low currents is adopted, by lithium ion battery to be changed, constant-current charge in stages, obtains the lithium after pre- chemical conversion
Ion battery, and stand；
B the first electric current) is adopted, the charge cutoff voltage of constant-current charge to lithium ion battery, then first time constant-voltage charge,
And stand again；
C the second electric current, the discharge cut-off voltage of constant-current discharge to lithium ion battery, and third time) is adopted to stand；
D) repeat step B) and C)；
E) the 3rd electric current, constant-current charge to the 4th voltage, again constant-voltage charge, the lithium-ion electric after being melted into are adopted
Pond.
Preferably, the value of the different low current is selected from 0.01～0.15C；
The hop count of the segmentation is 2～4 sections.
Preferably, step A) it is specially：
A1) low current A is adopted, by lithium ion battery to be changed, first constant-current charge is to first voltage；
A2) low current B is adopted, continues constant-current charge to second voltage；
A3 low current C) is adopted, again constant-current charge obtains the lithium ion battery after pre- chemical conversion to tertiary voltage, and quiet
Put.
Preferably, the low current A is 0.01～0.03C；The time of the constant-current charge first is 1～2h；Described
One voltage is 3.4～3.5V；
The low current B is 0.04～0.07C；The time for continuing constant-current charge is 1～2h；The second voltage is
3.75～3.8V；
The low current C is 0.08～0.15C；The time of the constant-current charge again is 1～2h；The tertiary voltage is
3.9～4.2V.
Preferably, the lithium ion battery to be changed is the lithium ion battery to be changed after pre-dwell；
The time of the pre-dwell is more than or equal to 1min；
The time of the standing is 20～60min.
Preferably, first electric current is 0.2～0.5C；Second electric current is 0.2～0.5C；3rd electric current is
0.2～0.5C；
The charge cutoff voltage of the lithium ion battery is 4.15～4.6V；
The first time constant-voltage charge is down to 0.02～0.05C to electric current；
The time for standing again is 5～15min.
Preferably, the discharge cut-off voltage of the lithium ion battery is 2.5～3.0V；
The time that the third time stands is 5～15min；
The repetition includes being repeated several times；Described is repeatedly 2～4 times；
4th voltage is more than or equal to 3.5V, and less than or equal to charge cutoff voltage；
The constant-voltage charge again is down to 0.02～0.05C to electric current.
Preferably, step A) in stand after also include：
Electric discharge and continuation stand step.
Preferably, the electric discharge and continuation stands step and is specially：
Using the 4th electric current, the discharge cut-off voltage of constant-current discharge to lithium ion battery, and continue to stand；
4th electric current is 0.2～0.5C；
The time for continuing to stand is 5～15min.
The present invention a kind of lithium ion battery is also provided, the lithium after chemical conversion by prepared by above-mentioned technical proposal any one from
Sub- battery, it is collated after obtain.
The invention provides a kind of chemical synthesizing method of lithium ion battery, comprises the following steps, initially with different low electricity
Stream, by lithium ion battery to be changed, constant-current charge in stages, obtains the lithium ion battery after pre- chemical conversion, and stands；Then adopt
First electric current, the charge cutoff voltage of constant-current charge to lithium ion battery, then first time constant-voltage charge, and stand again；Again
Using the second electric current, the discharge cut-off voltage of constant-current discharge to lithium ion battery, and third time stand；Subsequent repeat step B) and
C)；Finally adopt the 3rd electric current, constant-current charge to the 4th voltage, again constant-voltage charge, the lithium ion battery after being melted into.With
Prior art is compared, and the present invention need in the problem that improved for existing lithium battery integrated performance, selects in battery material
And selected in the multiple steps for preparing, start with from the chemical synthesis technology of battery, fill in the formation process of lithium battery, the i.e. first run
In electric process, it is divided into pre- chemical conversion and main chemical conversion step, is melted into using the segmentation of low pressure trickle in leading portion SEI films formation stages, effectively
Prevent solvation Li ion to be embedded in altogether, cause negative material to peel off；And by being segmented chemical synthesizing method using low pressure trickle, have
The time of SEI films densification composition " growth " is increased to effect, formation effect is more preferable；Again the present invention is also filled by the back segment being melted into
Discharge cycles process, effectively stabilizes the composition structure of SEI films, makes the structure of SEI films more stable, on negative material surface
Finer and close SEI films are formed, but also has preliminarily formed " track " that Li ions are embedded in abjection, can more effectively play battery
Capacity, improve lithium battery combination property.
Test result indicate that, the low pressure trickle provided using this invention is segmented the battery of chemical synthesizing method, and its SEI film is formed more
Densification, so as to have more preferable cycle performance.
Description of the drawings
Fig. 1 is the schematic diagram of the formation of lithium ion battery negative material surface SEI films；
Fig. 2 is the capacity distribution map of the lithium battery after the chemical conversion of the embodiment of the present invention 1；
Fig. 3 is the cycle performance pair of the lithium battery after the chemical conversion of the embodiment of the present invention 1 and the lithium battery after conventional method chemical conversion
Compare curve map.
Specific embodiment
In order to further appreciate that the present invention, the preferred embodiments of the invention are described with reference to embodiment, but
It is it should be appreciated that these descriptions are simply to further illustrate the features and advantages of the present invention rather than to patent requirements of the present invention
Limit.
The all raw materials of the present invention, originate to it and are not particularly limited, commercially buying or according to people in the art
Known to member prepared by conventional method.
The all raw materials of the present invention, are not particularly limited to its purity, present invention preferably employs analyzing pure lithium ion battery neck
Commonly use purity in domain.
The invention provides a kind of chemical synthesizing method of lithium ion battery, comprises the following steps：
A) different low currents is adopted, by lithium ion battery to be changed, constant-current charge in stages, obtains the lithium after pre- chemical conversion
Ion battery, and stand；
B the first electric current) is adopted, the charge cutoff voltage of constant-current charge to lithium ion battery, then first time constant-voltage charge,
And stand again；
C the second electric current, the discharge cut-off voltage of constant-current discharge to lithium ion battery, and third time) is adopted to stand；
D) repeat step B) and C)；
E) the 3rd electric current, constant-current charge to the 4th voltage, again constant-voltage charge, the lithium-ion electric after being melted into are adopted
Pond.
The present invention is not particularly limited to the lithium ion battery, and its standard and component type are not particularly limited, with
Lithium ion battery well known to those skilled in the art, those skilled in the art can want according to practical condition, quality
Ask and properties of product selected and adjusted, lithium ion battery of the present invention preferably using conventional kind and standard lithium from
Sub- battery, its normal voltage (rated voltage), discharge and recharge blanking voltage, normal capacity are this area usual definition or mark
It is accurate.
The present invention, by lithium ion battery to be changed, constant-current charge in stages, obtains pre-ization initially with different low currents
Lithium ion battery into after, and stand.
The present invention lithium ion battery to be changed is not particularly limited, with lithium well known to those skilled in the art from
In sub- cell manufacturing process, the battery semi-finished product before formation process, those skilled in the art can be according to actual production
Situation, quality requirement and properties of product are selected and adjusted, and the present invention is the further chemical conversion effect for lifting the pre- chemical conversion stage
Really, improve final product combination property, the lithium ion battery to be changed be preferably the lithium to be changed after pre-dwell from
Sub- battery.The present invention is not particularly limited to the time of the pre-dwell, is with time of repose well known to those skilled in the art
Can, those skilled in the art can be selected and be adjusted according to practical condition, quality requirement and properties of product, this
The time of the bright pre-dwell is preferably greater than equal to 1min, more preferably more preferably 1～10min, 3～8min, most preferably
For 5～6min, 1min is specifically as follows.
The present invention is not particularly limited to the range of choice of the different low current, and those skilled in the art can basis
Practical condition, quality requirement and properties of product are selected and adjusted, and the value of different low current of the present invention is excellent
Selected from 0.01～0.15C, 0.03～0.13C can be selected from, it is also possible to selected from 0.05～0.10C, it is also possible to selected from 0.07～
0.08C, or in the range of choice, multiple numerical value are selected, constitute different low currents.The list of charging current of the present invention
Position meets the common usage of this area using C, and wherein 1C represents the single lithium ion battery normal cell capacity (mAh).
The present invention is not particularly limited to the hop count of the segmentation, and those skilled in the art can be according to actual production feelings
Condition, quality requirement and properties of product are selected and adjusted, and the hop count of segmentation of the present invention is preferably 2～4 sections, more preferably
For 3～4 sections, most preferably 3 sections.
The present invention is the formation effect for further lifting the chemical conversion stage in advance, improves the combination property of final product, the step
Rapid A) it is particularly preferred as：
A1) low current A is adopted, by lithium ion battery to be changed, first constant-current charge is to first voltage；
A2) low current B is adopted, continues constant-current charge to second voltage；
A3 low current C) is adopted, again constant-current charge obtains the lithium ion battery after pre- chemical conversion to tertiary voltage, and quiet
Put.
The present invention is not particularly limited to the concrete numerical value of the low current A, with the low electricity of those skilled in the art's numerical value
Stream, those skilled in the art can be selected and be adjusted according to practical condition, quality requirement and properties of product,
The current value of low current A of the present invention is preferably 0.01～0.03C, more preferably 0.015～0.025C, most preferably
0.02C。
The present invention is not particularly limited to the time of the constant-current charge first, with the charging of those skilled in the art's numerical value
Time, those skilled in the art can be selected and be adjusted according to practical condition, quality requirement and properties of product
It is whole, time of constant-current charge first of the present invention be preferably 1～2h, more preferably 1.2～1.8h, most preferably 1.4～
1.6h, is specifically as follows 1h.
The present invention is not particularly limited to the numerical value of the first voltage, and those skilled in the art can be according to actual production
Situation, quality requirement and properties of product are selected and adjusted, and first voltage of the present invention is preferably 3.4～3.5V, more
Preferably 3.42～3.48V, most preferably 3.44～3.46V.
The present invention is not particularly limited to the concrete numerical value of the low current B, with the low electricity of those skilled in the art's numerical value
Stream, those skilled in the art can be selected and be adjusted according to practical condition, quality requirement and properties of product,
The current value of low current B of the present invention is preferably 0.04～0.07C, most preferably more preferably 0.05～0.06C, 0.05C.
The present invention is not particularly limited to the time of the continuation constant-current charge, with the charging of those skilled in the art's numerical value
Time, those skilled in the art can be selected and be adjusted according to practical condition, quality requirement and properties of product
It is whole, it is of the present invention continue constant-current charge time be preferably 1～2h, more preferably 1.2～1.8h, most preferably 1.4～
1.6h, is specifically as follows 1h.
The present invention is not particularly limited to the numerical value of the second voltage, and those skilled in the art can be according to actual production
Situation, quality requirement and properties of product are selected and adjusted, and second voltage of the present invention is preferably 3.75～3.8V, more
Preferably 3.76～3.79V, most preferably 3.77～3.78V.
The present invention is not particularly limited to the concrete numerical value of the low current C, with the low electricity of those skilled in the art's numerical value
Stream, those skilled in the art can be selected and be adjusted according to practical condition, quality requirement and properties of product,
The current value of low current C of the present invention be preferably 0.08～0.15C, more preferably 0.09～0.14C, more preferably 0.10～
0.13C, most preferably 0.11～0.12C, are specifically as follows 0.1C.
The present invention is not particularly limited to the time of the constant-current charge again, with the charging of those skilled in the art's numerical value
Time, those skilled in the art can be selected and be adjusted according to practical condition, quality requirement and properties of product
It is whole, time of constant-current charge again of the present invention be preferably 1～2h, more preferably 1.2～1.8h, most preferably 1.4～
1.6h, is specifically as follows 2h.
The present invention is not particularly limited to the numerical value of the tertiary voltage, and those skilled in the art can be according to actual production
Situation, quality requirement and properties of product are selected and adjusted, and tertiary voltage of the present invention is preferably 3.9～4.2V, more
Preferably 3.9～4.1V, most preferably 4.0～4.1V.
The present invention is the formation effect for further lifting pre- chemical conversion stage and main chemical conversion stage, improves the synthesis of final product
Performance, the lithium ion battery after the pre- chemical conversion need to be through standing step.The present invention is to the time of the standing without especially limit
System, with time of repose well known to those skilled in the art, those skilled in the art can be according to practical condition, quality
Require and properties of product are selected and adjusted, time of standing of the present invention is preferably 20～60min, more preferably 25
～55min, more preferably 30～50min, most preferably 35～45min, are specifically as follows 30min.
The present invention is the pre- chemical conversion of lifting and the formation effect in main chemical conversion stage, it is ensured that the combination property of final product, described
Battery after standing may also pass through electric discharge and continue to stand step.The present invention is to the electric discharge and continues the concrete steps for standing
It is not particularly limited with parameter, with above-mentioned steps well known to those skilled in the art, those skilled in the art can basis
Practical condition, quality requirement and properties of product are selected and adjusted, and electric discharge of the present invention and continuation stand step
It is particularly preferred as, using the 4th electric current, the discharge cut-off voltage of constant-current discharge to lithium ion battery, and continues to stand.
The present invention is not particularly limited to the concrete numerical value of the 4th electric current, with electric discharge well known to those skilled in the art
Electric current, those skilled in the art can be selected and be adjusted according to practical condition, quality requirement and properties of product
Whole, the first electric current of the present invention is preferably 0.2～0.5C, most preferably more preferably 0.25～0.45C, 0.3～0.4C, tool
Body can be 0.2C.
The present invention is not particularly limited to the time for continuing to stand, with time of repose well known to those skilled in the art
, those skilled in the art can be selected and be adjusted according to practical condition, quality requirement and properties of product, this
The invention time for continuing to stand is preferably 5～15min, more preferably more preferably 7～13min, 8～12min, most preferably
For 9～11min, 10min is specifically as follows.
The present invention is not particularly limited to the concrete numerical value of the discharge cut-off voltage of the lithium ion battery, with this area skill
The discharge cut-off voltage of lithium ion battery known to art personnel, those skilled in the art can according to practical condition,
Quality requirement and properties of product are selected and adjusted, and the discharge cut-off voltage of lithium ion battery of the present invention is preferably
2.5～3.0V, more preferably 2.8～3.0V, more preferably 2.9～3.0V, most preferably 3.0V, be specifically as follows 2.95V or
3.0V。
The present invention and then the first electric current is adopted, the charge cutoff voltage of constant-current charge to lithium ion battery, then for the first time
Constant-voltage charge, and stand again.
The present invention is not particularly limited to the concrete numerical value of first electric current, with charging well known to those skilled in the art
Electric current, those skilled in the art can be selected and be adjusted according to practical condition, quality requirement and properties of product
Whole, the first electric current of the present invention is preferably 0.2～0.5C, most preferably more preferably 0.25～0.45C, 0.3～0.4C, tool
Body can be 0.2C.
The present invention is not particularly limited to the concrete numerical value of the charge cutoff voltage of the lithium ion battery, with this area skill
The charge cutoff voltage of lithium ion battery known to art personnel, those skilled in the art can according to practical condition,
Quality requirement and properties of product are selected and adjusted, and the charge cutoff voltage of lithium ion battery of the present invention is preferably
4.15～4.6V, more preferably 4.25～4.5V, most preferably 4.35～4.4V, are specifically as follows 4.2V, 4.35V or 4.4V.
The present invention is not particularly limited to the design parameter of the first time constant-voltage charge, is known with those skilled in the art
Constant-voltage charge parameter, those skilled in the art can be according to practical condition, quality requirement and properties of product
Selected and adjusted, the cutoff current value of first time constant-voltage charge of the present invention is preferably 0.02～0.05C, i.e., described
Constant-voltage charge a to charging current is preferably dropped to 0.02～0.05C, more preferably 0.025～0.045C, most preferably 0.03
～0.04C, is specifically as follows 0.02C.
The present invention is not particularly limited to the time for standing again, with time of repose well known to those skilled in the art
, those skilled in the art can be selected and be adjusted according to practical condition, quality requirement and properties of product, this
The time stood again described in invention is preferably 5～15min, more preferably more preferably 7～13min, 8～12min, most preferably
For 9～11min, 10min is specifically as follows.
The present invention adopts again the second electric current, the discharge cut-off voltage of constant-current discharge to lithium ion battery, and third time to stand.
The present invention is not particularly limited to the concrete numerical value of second electric current, with electric discharge well known to those skilled in the art
Electric current, those skilled in the art can be selected and be adjusted according to practical condition, quality requirement and properties of product
Whole, the second electric current of the present invention is preferably 0.2～0.5C, most preferably more preferably 0.25～0.45C, 0.3～0.4C, tool
Body can be 0.2C.
The present invention is not particularly limited to the concrete numerical value of the discharge cut-off voltage of the lithium ion battery, with this area skill
The discharge cut-off voltage of lithium ion battery known to art personnel, those skilled in the art can according to practical condition,
Quality requirement and properties of product are selected and adjusted, and the discharge cut-off voltage of lithium ion battery of the present invention is preferably
2.5～3.0V, more preferably 2.8～3.0V, more preferably 2.9～3.0V, most preferably 3.0V, be specifically as follows 2.95V or
3.0V。
The present invention is not particularly limited to the time that the third time stands, during with standing well known to those skilled in the art
Between, those skilled in the art can be selected and be adjusted according to practical condition, quality requirement and properties of product,
The time that third time of the present invention stands is preferably 5～15min, more preferably more preferably 7～13min, 8～12min, most
Preferably 9～11min, is specifically as follows 10min.
Subsequently repeat the above steps B of the invention) and C).
The present invention is the formation effect for lifting the main chemical conversion stage, it is ensured that the combination property of final product, the present invention is above-mentioned heavy
Again number can also be to be repeated several times.The present invention is not particularly limited to the repeated concrete number of times, art technology
Personnel can be selected and be adjusted according to practical condition, quality requirement and properties of product, many suboptimums of the present invention
Elect as 2～4 times, or for 3 times, most preferably 2 times.
It is of the invention finally to adopt the 3rd electric current, constant-current charge to the 4th voltage, constant-voltage charge again, the lithium after being melted into
Ion battery.
The present invention is not particularly limited to the concrete numerical value of the 3rd electric current, with charging well known to those skilled in the art
Electric current, those skilled in the art can be selected and be adjusted according to practical condition, quality requirement and properties of product
Whole, the 3rd electric current of the present invention is preferably 0.2～0.5C, most preferably more preferably 0.25～0.45C, 0.3～0.4C, tool
Body can be 0.2C.
The present invention is not particularly limited to the concrete numerical value of the 4th voltage, with charging well known to those skilled in the art
Voltage, those skilled in the art can be selected and be adjusted according to practical condition, quality requirement and properties of product
Whole, the 4th voltage of the present invention is preferably greater than equal to 3.5V, and less than or equal to charge cutoff voltage, more preferably 3.6～
4.3V, more preferably 3.7～4.2V, more preferably 3.9～4.1V, most preferably 4.0～4.1V, are specifically as follows 4.0V.
The present invention is not particularly limited to the design parameter of the constant-voltage charge again, with well known to those skilled in the art
The parameter of constant-voltage charge, those skilled in the art can enter according to practical condition, quality requirement and properties of product
Row is selected and adjusted, and the cutoff current value of constant-voltage charge again of the present invention is preferably 0.02～0.05C, i.e., described permanent again
Pressure charges to charging current and is preferably dropped to 0.02～0.05C, more preferably 0.025～0.045C, most preferably 0.03～
0.04C, is specifically as follows 0.02C.
Referring to Fig. 1, Fig. 1 is the schematic diagram of the formation of lithium ion battery negative material surface SEI films.
The present invention a kind of lithium ion battery is also provided, the lithium after chemical conversion by prepared by above-mentioned technical proposal any one from
Sub- battery, it is collated after obtain.
The present invention is not particularly limited to the concrete steps and parameter of the arrangement, with well known to those skilled in the artization
Lithium ion battery into after makes the step required for resultant battery, and those skilled in the art can be according to actual production feelings
Condition, quality requirement and properties of product are selected and adjusted, and can include the steps such as two envelopes, partial volume and ageing, it is also possible to will
Battery after chemical conversion is directly as resultant battery.
The invention provides a kind of chemical synthesizing method of the lithium ion battery that can form fine and close SEI films, the present invention is for existing
Some lithium battery integrated performances need in the problem that improved, battery material select and multiple steps for preparing in selected
Select, start with from the chemical synthesis technology of battery, in the formation process of lithium battery, i.e. first run charging process, be divided into pre- chemical conversion and mainization
Into step, in leading portion SEI films formation stages using the segmentation chemical conversion of low pressure trickle, the segmentation of particularly different specific current value
Chemical conversion, is effectively prevented solvation Li ion and is embedded in altogether, causes negative material to peel off；And by using low pressure trickle section
Into method, the time of SEI films densification composition " growth " is effectively increased, formation effect is more preferable；Again the present invention is also by changing
Into back segment charge and discharge cycles process, especially the charge and discharge cycles process of multi-step special parameter, effectively stabilizes SEI films
Composition structure, make the structure of SEI films more stable, form finer and close SEI films on negative material surface, but also tentatively
Define " track " that Li ions are embedded in abjection, can more effectively play the capacity of battery, improve the combination property of lithium battery.
Test result indicate that, the low pressure trickle provided using this invention is segmented the battery of chemical synthesizing method, and its SEI film is formed more
Densification, so as to have more preferable cycle performance.
In order to further illustrate the present invention, a kind of chemical conversion of the present invention is provided lithium ion battery with reference to embodiments
Method is described in detail, but it is to be understood that these embodiments are implemented under premised on technical solution of the present invention,
Detailed embodiment and specific operating process are given, simply to further illustrate the features and advantages of the present invention, and not
It is limiting to the claimed invention, protection scope of the present invention is also not necessarily limited to following embodiments.
Embodiment 1
Positive pole is with LCO:SP:CNT:HSV900=96.3:1.3:0.4:Material is stirred in 2 ratio mixing, with NMP as solvent, is applied
Overlay on and make on aluminium foil positive plate, surface density is 420g/m2.Negative pole is with C:SP:CNT:CMC:SBR=95:1.2:0.5:1.3:
Material is stirred in 2.0 ratio mixing, with water as solvent, is coated on Copper Foil and is made negative plate, and surface density is 212g/m2.Electrolyte is adopted
With the LiPF of 1mol/L6EC, DMC and EMC (volume ratio is 1：1:1) solution.Make the 4.4V lithium ion Soft Rolls of 3000mAh
After battery.
It is melted into using following chemical synthesizing methods, is formed SEI films.
Pre- formation process：
1) 1min is shelved；
2) 0.02C CC (constant-current charge) 1h, blanking voltage is 3.5V；
3) 0.05C CC 1h, blanking voltage is 3.75V；
4) 0.1C CC 2h, blanking voltage is 4.1V.
Main formation process：
1) 30min is shelved；
2) 0.2C CC (300min) arrive 4.4V, and 4.4V CV (constant-voltage charge) arrive 0.02C (120min)；
3) 10min is shelved；
4) 0.2C DC (constant-current discharge) arrive 3.0V；
5) 10min is shelved；
6) circulation 2)～5) twice；
7) 0.2C CC to 4.0V, 4.0V CV to 0.02C；
8) 10min is shelved.
Lithium battery after being melted into above-mentioned steps, by carry out battery 0.5C charge and discharges cycle performance test and and
Before and after circulation the variable quantity of thickness come judge SEI formed fine and close effect.
Referring to Fig. 2, Fig. 2 is the capacity distribution map of the lithium battery after the chemical conversion of the embodiment of the present invention 1.As shown in Figure 2, the present invention
Formation effect, uniformity is fine.
Referring to Fig. 3, Fig. 3 is following for the lithium battery after the lithium battery and conventional method after the chemical conversion of the embodiment of the present invention 1 is melted into
Ring performance comparison curve map.
And after cycle performance test, the cell thickness changing value of present invention chemical conversion is about≤0.2mm；And adopt normal
The cell thickness changing value for advising chemical synthesizing method is 0.2～0.4mm, and this shows, the SEI films densification effect that the present invention is formed is more preferable,
Repeat " growth " unobvious.What side reaction occurred in cyclic process is less.
Embodiment 2
Positive pole is with LCO:SP:CNT:HSV900=96.3:1.3:0.4:Material is stirred in 2 ratio mixing, with NMP as solvent, is applied
Overlay on and make on aluminium foil positive plate, surface density is 420g/m2.Negative pole is with C:SP:CNT:CMC:SBR=95:1.2:0.5:1.3:
Material is stirred in 2.0 ratio mixing, with water as solvent, is coated on Copper Foil and is made negative plate, and surface density is 212g/m2.Electrolyte is adopted
With the LiPF of 1mol/L6EC, DMC and EMC (volume ratio is 1：1:1) solution.Make the 4.4V lithium ion Soft Rolls of 3000mAh
After battery.
Pre- formation process：
1) 1min is shelved；
2) 0.02C CC (constant-current charge) 1h, blanking voltage is 3.4V；
3) 0.05C CC 1h, blanking voltage is 3.8V；
4) 0.1C CC 2h, blanking voltage is 4.0V.
Main formation process：
1) 40min is shelved；
2) 0.2C CC to 4.35V, 4.35V CV to 0.03C；
3) 8min is shelved；
4) 0.2C DC to 3.0V (electric discharge of lithium battery is by voltage)；
5) 12min is shelved；
7) 0.2C CC to 4.0V, 4.0V CV to 0.02C.(can omit)
Lithium battery after being melted into above-mentioned steps, by carry out battery 0.5C charge and discharges cycle performance test and and
Before and after circulation the variable quantity of thickness come judge SEI formed fine and close effect.
Testing result shows that lithium battery prepared by the embodiment of the present invention 2, formation effect uniformity is fine.
Embodiment 3
Positive pole is with LCO:SP:CNT:HSV900=96.3:1.3:0.4:Material is stirred in 2 ratio mixing, with NMP as solvent, is applied
Overlay on and make on aluminium foil positive plate, surface density is 420g/m2.Negative pole is with C:SP:CNT:CMC:SBR=95:1.2:0.5:1.3:
Material is stirred in 2.0 ratio mixing, with water as solvent, is coated on Copper Foil and is made negative plate, and surface density is 212g/m2.Electrolyte is adopted
With the LiPF of 1mol/L6EC, DMC and EMC (volume ratio is 1：1:1) solution.Make the 4.4V lithium ion Soft Rolls of 3000mAh
After battery.
Pre- formation process：
1) 1min is shelved；
2) 0.02C CC (constant-current charge) 1h, blanking voltage is 3.45V；
3) 0.05C CC 1h, blanking voltage is 3.V；
4) 0.1C CC 2h, blanking voltage is 4.05V.
Main formation process：
1) 20min is shelved；
2) 0.2C DC to 3.0V (electric discharge of lithium battery is by voltage)；
3) 15min is shelved；(time >=5min)
4) 0.2C CC to 4.2V, 4.4V CV to 0.05C；
5) 10min is shelved
6) 0.2C DC to 3.0V (electric discharge of lithium battery is by voltage)；
8) 0.2C CC to 4.0V, 4.0V CV to 0.02C.(can omit)
Lithium battery after being melted into above-mentioned steps, by carry out battery 0.5C charge and discharges cycle performance test and and
Before and after circulation the variable quantity of thickness come judge SEI formed fine and close effect.
Testing result shows that lithium battery prepared by the embodiment of the present invention 3, formation effect uniformity is fine.
A kind of chemical synthesizing method of the lithium ion battery that can form fine and close SEI films for providing the present invention above has been carried out in detail
Thin introduction, specific case used herein is set forth to the principle and embodiment of the present invention, above example
Illustrate that being only intended to help understands the method for the present invention and its core concept, including best mode, and also cause this area
Any technical staff can put into practice the present invention, including manufacture and using any device or system, and implement the side of any combination
Method.It should be pointed out that for those skilled in the art, under the premise without departing from the principles of the invention, may be used also
To carry out some improvement and modification to the present invention, these are improved and modification is also fallen into the protection domain of the claims in the present invention.
The scope of patent protection of the present invention is defined by the claims, and may include those skilled in the art it is conceivable that other realities
Apply example.If these other embodiments have is not different from the structural element of claim character express, or if they
Including with equivalent structural elements of the character express of claim without essence difference, then these other embodiments also should be included in
In the range of claim.
Claims (10)
1. a kind of chemical synthesizing method of lithium ion battery, it is characterised in that comprise the following steps：
A) different low currents is adopted, by lithium ion battery to be changed, constant-current charge in stages, obtains the lithium ion after pre- chemical conversion
Battery, and stand；
B the first electric current) is adopted, the charge cutoff voltage of constant-current charge to lithium ion battery, then first time constant-voltage charge, and again
Secondary standing；
C the second electric current, the discharge cut-off voltage of constant-current discharge to lithium ion battery, and third time) is adopted to stand；
D) repeat step B) and C)；
E) the 3rd electric current, constant-current charge to the 4th voltage, again constant-voltage charge, the lithium ion battery after being melted into are adopted.
2. chemical synthesizing method according to claim 1, it is characterised in that the value of the different low current selected from 0.01～
0.15C；
The hop count of the segmentation is 2～4 sections.
3. chemical synthesizing method according to claim 1, it is characterised in that step A) it is specially：
A1) low current A is adopted, by lithium ion battery to be changed, first constant-current charge is to first voltage；
A2) low current B is adopted, continues constant-current charge to second voltage；
A3) low current C is adopted, again constant-current charge obtains the lithium ion battery after pre- chemical conversion to tertiary voltage, and stands.
4. chemical synthesizing method according to claim 3, it is characterised in that the low current A is 0.01～0.03C；The head
The time of secondary constant-current charge is 1～2h；The first voltage is 3.4～3.5V；
The low current B is 0.04～0.07C；The time for continuing constant-current charge is 1～2h；The second voltage is 3.75
～3.8V；
The low current C is 0.08～0.15C；The time of the constant-current charge again is 1～2h；The tertiary voltage is 3.9
～4.2V.
5. the chemical synthesizing method according to Claims 1 to 4 any one, it is characterised in that the lithium-ion electric to be changed
Pond is the lithium ion battery to be changed after pre-dwell；
The time of the pre-dwell is more than or equal to 1min；
The time of the standing is 20～60min.
6. chemical synthesizing method according to claim 1, it is characterised in that first electric current is 0.2～0.5C；Described second
Electric current is 0.2～0.5C；3rd electric current is 0.2～0.5C；
The charge cutoff voltage of the lithium ion battery is 4.15～4.6V；
The first time constant-voltage charge is down to 0.02～0.05C to electric current；
The time for standing again is 5～15min.
7. chemical synthesizing method according to claim 1, it is characterised in that the discharge cut-off voltage of the lithium ion battery is
2.5～3.0V；
The time that the third time stands is 5～15min；
The repetition includes being repeated several times；Described is repeatedly 2～4 times；
4th voltage is more than or equal to 3.5V, and less than or equal to charge cutoff voltage；
The constant-voltage charge again is down to 0.02～0.05C to electric current.
8. chemical synthesizing method according to claim 1, it is characterised in that step A) in stand after also include：
Electric discharge and continuation stand step.
9. chemical synthesizing method according to claim 8, it is characterised in that the electric discharge and continue to stand step and be specially：
Using the 4th electric current, the discharge cut-off voltage of constant-current discharge to lithium ion battery, and continue to stand；
4th electric current is 0.2～0.5C；
The time for continuing to stand is 5～15min.
10. a kind of lithium ion battery, it is characterised in that the lithium ion after chemical conversion by prepared by claim 1～9 any one
Battery, it is collated after obtain.
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101308943A (en) * | 2008-06-06 | 2008-11-19 | 恒正科技（苏州）有限公司 | Lithium ionic cell formation processing method |
| CN101615696A (en) * | 2009-07-16 | 2009-12-30 | 江苏富朗特新能源有限公司 | A kind of chemical synthesis technology of flexible packing lithium ion secondary battery |
| CN102324570A (en) * | 2011-09-07 | 2012-01-18 | 惠州Tcl金能电池有限公司 | Lithium ion battery, its formation method and preparation method |
-
2017
- 2017-01-22 CN CN201710053448.3A patent/CN106654427B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101308943A (en) * | 2008-06-06 | 2008-11-19 | 恒正科技（苏州）有限公司 | Lithium ionic cell formation processing method |
| CN101615696A (en) * | 2009-07-16 | 2009-12-30 | 江苏富朗特新能源有限公司 | A kind of chemical synthesis technology of flexible packing lithium ion secondary battery |
| CN102324570A (en) * | 2011-09-07 | 2012-01-18 | 惠州Tcl金能电池有限公司 | Lithium ion battery, its formation method and preparation method |
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