CN116885317A - Formation method of hard shell lithium ion battery - Google Patents
Formation method of hard shell lithium ion battery Download PDFInfo
- Publication number
- CN116885317A CN116885317A CN202311057076.3A CN202311057076A CN116885317A CN 116885317 A CN116885317 A CN 116885317A CN 202311057076 A CN202311057076 A CN 202311057076A CN 116885317 A CN116885317 A CN 116885317A
- Authority
- CN
- China
- Prior art keywords
- battery
- charging
- multiplying power
- standing
- formation
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 230000015572 biosynthetic process Effects 0.000 title claims abstract description 74
- 238000000034 method Methods 0.000 title claims abstract description 40
- HBBGRARXTFLTSG-UHFFFAOYSA-N Lithium ion Chemical compound [Li+] HBBGRARXTFLTSG-UHFFFAOYSA-N 0.000 title claims abstract description 26
- 229910001416 lithium ion Inorganic materials 0.000 title claims abstract description 26
- 238000007599 discharging Methods 0.000 claims abstract description 16
- 238000012545 processing Methods 0.000 claims description 3
- 230000001351 cycling effect Effects 0.000 claims description 2
- 239000003792 electrolyte Substances 0.000 abstract description 16
- 238000004519 manufacturing process Methods 0.000 abstract description 11
- 230000000052 comparative effect Effects 0.000 description 17
- 238000001816 cooling Methods 0.000 description 5
- 230000014759 maintenance of location Effects 0.000 description 5
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- 229910052744 lithium Inorganic materials 0.000 description 4
- 229910003002 lithium salt Inorganic materials 0.000 description 4
- 159000000002 lithium salts Chemical class 0.000 description 4
- 230000008595 infiltration Effects 0.000 description 3
- 238000001764 infiltration Methods 0.000 description 3
- 230000002427 irreversible effect Effects 0.000 description 3
- GELKBWJHTRAYNV-UHFFFAOYSA-K lithium iron phosphate Chemical compound [Li+].[Fe+2].[O-]P([O-])([O-])=O GELKBWJHTRAYNV-UHFFFAOYSA-K 0.000 description 3
- 230000010287 polarization Effects 0.000 description 3
- 230000002035 prolonged effect Effects 0.000 description 3
- 238000003860 storage Methods 0.000 description 3
- 238000012360 testing method Methods 0.000 description 3
- 230000009286 beneficial effect Effects 0.000 description 2
- 239000013078 crystal Substances 0.000 description 2
- 125000004122 cyclic group Chemical group 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 239000007772 electrode material Substances 0.000 description 2
- 230000002687 intercalation Effects 0.000 description 2
- 238000009830 intercalation Methods 0.000 description 2
- 239000002904 solvent Substances 0.000 description 2
- 238000009825 accumulation Methods 0.000 description 1
- 239000013543 active substance Substances 0.000 description 1
- 230000032683 aging Effects 0.000 description 1
- 238000009831 deintercalation Methods 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 150000002500 ions Chemical class 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000002161 passivation Methods 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 238000012797 qualification Methods 0.000 description 1
- 238000012216 screening Methods 0.000 description 1
Classifications
-
- 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
- H01M10/446—Initial charging measures
-
- 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
- H01M10/05—Accumulators with non-aqueous electrolyte
- H01M10/052—Li-accumulators
- H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
-
- 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
-
- 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
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
- Y02P70/50—Manufacturing or production processes characterised by the final manufactured product
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Manufacturing & Machinery (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- General Chemical & Material Sciences (AREA)
- Materials Engineering (AREA)
- Secondary Cells (AREA)
Abstract
The invention provides a hard shell lithium ion battery formation method, which comprises the following steps: s1, after the battery is injected, performing pre-formation treatment under the conditions that the pressure is-70 to-90 KPa and the temperature is 42-48 ℃, and forming the battery into an activated state by means of charging, standing and discharging for 70-150 min; s2, performing pre-circulation treatment under the conditions that the temperature is 22-28 ℃ and the pressure is in a negative pressure state, wherein the pre-circulation treatment comprises: pre-circulating charging, wherein the duration is 120-150 min, the charging current multiplying power is 0.2C, and the cut-off current multiplying power is 0.05C; pre-circulating and standing until the temperature of the battery is reduced to 22-28 ℃; pre-circulating discharge, wherein the duration is 120-150 min, the discharge current multiplying power is 0.2C, and the cut-off voltage is 2.5V; s3, ending charging is carried out for 60min, the charging current multiplying power is 0.5C, and the cut-off current multiplying power is 0.05C. The battery is formed in a pre-forming and pre-circulating mode, so that the problem that the electrolyte reserves are influenced due to long high-temperature formation time is avoided, and the battery formation time can be effectively shortened, and the production efficiency is improved.
Description
Technical Field
The invention relates to the technical field of battery formation, in particular to a hard shell lithium ion battery formation method.
Background
Lithium ion batteries are mainly classified into two types, cylindrical and square. In the production and preparation of liquid lithium ion batteries, the batteries are required to be formed to activate active substances in the batteries, a passivation layer, namely an SEI film, is formed on an electrode material in the process, and the cyclic performance and the service life of the batteries can be directly influenced by the SEI film. The formation process involves multiple charging and discharging and standing, and is slow, so that the formation process becomes one of the important bottlenecks for improving the manufacturing yield of the battery. The SEI film formation and battery formation improvement method is studied in depth, and is an effective way for improving battery performance and production efficiency.
The invention patent application with the publication number of CN114824524A discloses a formation method of a square aluminum-shell lithium iron phosphate battery, and relates to the field of lithium iron phosphate batteries; the invention adopts high temperature 45-50 ℃ standing aging before formation, and adopts a high temperature (40-80 ℃) negative pressure mode for formation.
In the technical scheme, the temperature range in the formation process is 40-80 ℃, the standing time is 24-72 hours, and long-time high-temperature standing can lead to expansion of a core pack in the battery, compress the space between a battery shell and the core pack, and lead to reduction of the storage amount of electrolyte, thereby influencing the cycle performance, the service life and the production efficiency of the battery. The invention patent with the publication number of CN107039699B discloses a formation method for improving the capacity consistency of an old hard-shell power lithium battery, which is characterized in that the battery is subjected to formation by standing at 30-50 ℃ and the expansion problem of the core pack is caused; secondly, the longer time of placement in this technique also affects the production efficiency of the battery.
The invention patent with the publication number of CN102403536B discloses a formation method of a cylindrical lithium battery, wherein only three-week half charge-discharge cycles are carried out in the formation process, and simultaneously, the formation of a battery negative electrode SEI film, capacity division and low-voltage screening of the battery are completed. The standing time is 49-62 hours, namely the battery is formed, and the time required for the battery to be formed is at least two days, so that the production efficiency of the battery can be obviously affected, and the yield is low.
From the above, the current formation process of lithium ion batteries mainly has the problems of core pack expansion, long production period and low yield caused by long-time high-temperature formation.
Disclosure of Invention
In view of the above, the invention provides a method for forming a hard shell lithium ion battery with short high-temperature formation time and short total formation time, so as to solve the problems of expansion of a core package and long production period caused by long-time standing due to the existing high-temperature formation.
The technical scheme of the invention is realized as follows: the invention provides a hard shell lithium ion battery formation method, which comprises the following steps:
s1, after the battery is injected, performing pre-formation treatment under the conditions that the pressure is-70 to-90 KPa and the temperature is 42-48 ℃, and forming the battery into an activated state by means of charging, standing and discharging for 70-150 min;
s2, performing pre-circulation treatment under the conditions that the temperature is 22-28 ℃ and the pressure is in a negative pressure state, wherein the pre-circulation treatment comprises: pre-circulating charging, wherein the duration is 120-150 min, the charging current multiplying power is 0.2C, and the cut-off current multiplying power is 0.05C; pre-circulating and standing until the temperature of the battery is reduced to 22-28 ℃; pre-circulating discharge, wherein the duration is 120-150 min, the discharge current multiplying power is 0.2C, and the cut-off voltage is 2.5V;
s3, ending charging is carried out for 60min, the charging current multiplying power is 0.5C, and the cut-off current multiplying power is 0.05C.
On the basis of the technical scheme, the negative pressure condition of the pre-circulation treatment is preferably-20 to-40 KPa.
Based on the above technical scheme, the temperature of the pre-circulation treatment is preferably 25 ℃.
On the basis of the technical scheme, the time period of pre-circulation standing is preferably 5-10 min.
Based on the above technical solution, preferably, in step 2, the number of cycles of the pre-cycle treatment is at least three.
On the basis of the above technical scheme, preferably, the pre-formation treatment comprises at least two charging, one discharging and three standing;
the processing steps are as follows: first standing, first charging, second standing, pre-formation discharging, third standing and second charging.
Based on the technical scheme, the single standing time is preferably 1-10 min.
On the basis of the technical scheme, preferably, the duration of the first charging is 5-10 min, the charging current multiplying power is 0.2C, the cut-off voltage is 3.65V, and the cut-off current is 0.05C.
On the basis of the technical scheme, the duration of the pre-formation discharge is preferably 5-10 min, the discharge current multiplying power is 0.5C, and the cut-off voltage is preferably 2.5V.
Based on the technical scheme, the duration of the second charging is preferably 60-80 min, the charging current multiplying power is 0.5C, and the cut-off current is preferably 0.05C.
Compared with the prior art, the hard shell lithium ion battery formation method has the following beneficial effects:
(1) The battery is formed in a high-temperature (42-48 ℃) and normal-temperature (22-28 ℃) mode, so that the problem that the core package expands and the electrolyte reserve is influenced due to overlong high-temperature formation time can be effectively avoided; secondly, the formation method of the combination mode controls the formation total duration within 7-20 hours on the premise of ensuring the battery performance, and can effectively shorten the battery formation duration, thereby improving the production efficiency;
(2) In the pre-formation treatment and the pre-circulation treatment, the charging current multiplying power is increased from small to large, the formation of the small current multiplying power is easier to generate single-electron reaction, the generation of inorganic lithium salt components is facilitated, the ordered accumulation of SEI film molecules is facilitated, the structure is more compact, and the battery performance is improved; when the current multiplying power is high, double-electron reaction is easier to occur, namely two electrons participate in the reaction at the same time, organic lithium salt components are correspondingly easier to generate, at the moment, SEI film molecules are more easily stacked in disorder, the structure is more loose, irreversible reaction is more, more electrolyte can be infiltrated by the loose SEI film, and the ion conductivity is high; the SEI film crystal nucleus forming speed is high; the stepped current multiplying power formation from small to large is beneficial to reducing the polarization level of the battery, so that the charging capacity is improved, the charging time is shortened, and the formation efficiency is improved.
Drawings
In order to more clearly illustrate the embodiments of the invention or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, it being obvious that the drawings in the following description are only some embodiments of the invention, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
Fig. 1 is a diagram showing a battery cycle capacity map obtained in accordance with an embodiment of the formation method of a hard-shell lithium ion battery of the present invention;
FIG. 2 is a graph of battery cycle capacity without pre-cycling treatment (comparative example one);
fig. 3 is a process diagram of a hard shell lithium ion battery formation method of the present invention;
Detailed Description
The following description of the embodiments of the present invention will clearly and fully describe the technical aspects of the embodiments of the present invention, and it is apparent that the described embodiments are only some embodiments of the present invention, not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the present invention without making any inventive effort, are intended to fall within the scope of the present invention.
The hard shell lithium ion battery formation method comprises the following steps:
s1, after the battery is injected, performing pre-formation treatment under the conditions that the pressure is-70 to-90 KPa and the temperature is 42-48 ℃, and forming the battery into an activated state by means of charging, standing and discharging for 70-150 min;
specifically, the pre-formation treatment comprises at least two times of charging, one time of discharging and three times of standing; the processing steps are as follows: first standing, first charging, second standing, pre-formation discharging, third standing and second charging.
Wherein the duration of single standing is 1-10 min.
Preferably, the first standing time is 5min, the second standing time is 10min, and the third standing time is 1min.
The duration of the first charge is 5-10 min, the charging current multiplying power is 0.5C, the cut-off voltage is 3.65V, and the cut-off current is 0.05C.
The duration of the pre-formation discharge is 5-10 min, the discharge current multiplying power is 0.5C, and the cut-off voltage is 2.5V.
The second charging time is 60-80 min, the charging current multiplying power is 0.5C, and the cut-off current is 0.05C.
As described above, the battery is subjected to three steps of standing, twice charging and once discharging, and like conventional battery formation, three steps of charging and twice discharging are generally adopted, which consumes a long time, so that the problem of long battery formation time needs to be solved;
in the technical scheme, the time length of the first charging is 5-10 min, and the battery is charged for as long as possible in the first charging process, preferably 10min, so that the positive and negative pole pieces of the battery fully absorb electrolyte, the infiltration effect of the pole pieces is ensured, the consistency of the reaction interfaces of the positive and negative pole pieces is further ensured, the charging and discharging energy efficiency of the battery is improved, and the service life is prolonged.
In the second charging process, the preferred time is 60min, which makes the battery in the state of charge, is favorable for the storage of the battery, ensures a stable voltage internal resistance interval, is convenient for the grouping between the batteries, and makes the battery in the state of charge without long-time charging, so that the secondary charging is only needed for 60 min.
From the above, if the highest duration is adopted for the two charging, the one discharging and the three standing, the total duration is 130min, and the shortest duration is 73min for the two charging, the one discharging and the three standing, compared with the prior art, the time for forming the battery under the high temperature condition is greatly reduced, the internal space of the battery caused by long-time thermal expansion of the battery core package can be avoided, the influence on the reserve of electrolyte is avoided, the battery can store more electrolyte, and the service life of the battery is prolonged.
In order to further improve the performance of the battery and prolong the service life of the battery, the formation method also carries out pre-circulation treatment, and in order to ensure the uniform and stable formation of SEI, the pre-circulation treatment is carried out at least three times.
Specifically, step S2 is executed, and the pre-cycle treatment is performed under the conditions that the temperature is 22 to 28 ℃ and the pressure is in a negative pressure state, wherein the pre-cycle treatment includes: pre-circulating charging, wherein the duration is 120-150 min, the charging current multiplying power is 0.2C, and the cut-off current multiplying power is 0.05C; pre-circulating and standing until the temperature of the battery is reduced to 22-28 ℃; pre-circulating discharge is carried out for 120-150 min, the discharge current multiplying power is 0.2C, and the cut-off voltage is 2.5V.
The negative pressure condition is preferably-20 to-40 KPa.
In the formation process, the pressure is too high to have free electrolyte, and too low pressure can lead to the incapable discharge of gas generated by formation, so that the pressure condition of pre-circulation is preferably set to be-30 Kpa, the electrolyte and the positive and negative plates can be ensured to be fully contacted, the electrolyte is better absorbed by the positive and negative plates, and the infiltration effect of the positive and negative plates is improved.
Like conventional battery formation, the formation is generally carried out under the conditions of high temperature (42-48 ℃) and high voltage (-80 KPa), and the formation time is long, which causes expansion of a battery core pack, compresses the internal space of a battery, further influences the storage capacity of electrolyte, and causes poor battery cycle performance;
meanwhile, when the battery is subjected to formation, only the battery is subjected to the pretreatment at a high temperature (42-48 ℃) and a high pressure (-80 KPa), and when the battery is subjected to the pretreatment, the battery is subjected to the pretreatment at a temperature of 22-28 ℃, and meanwhile, the pressure range is selected from the conditions of-20 KPa to-40 KPa and the temperature of 22-28 ℃ to be close to room temperature, so that the expansion of a core package of the battery caused by the overhigh temperature can be avoided, and further, the battery can store more electrolyte, so that the cycle life is ensured.
After the pre-circulation treatment, executing a step S3, and performing constant-current constant-voltage ending charging for 60min, wherein the charging current multiplying power is 0.5C, and the cut-off current multiplying power is 0.05C.
As described above, the pre-cycle temperature is 22 to 28 ℃, and is actually at normal temperature, which can prevent the high temperature from affecting the capacity of the battery during pre-cycle, and it is preferable that the pre-cycle is allowed to stand at 25 ℃ in order to reduce the battery temperature, so that the pre-cycle effect and the pre-cycle efficiency can be both achieved. Furthermore, the standing time of the pre-circulation is 5-10 min, so that the cooling requirement can be met.
As described above, the rest time adopted by the pre-cycle is only 5-10 min, which is used for cooling the battery after the pre-formation treatment, so that the battery can perform the pre-cycle treatment, and meanwhile, the high efficiency of the battery formation is ensured, of course, the cooling of the battery can be influenced by the environment, and auxiliary measures such as air cooling can be adopted to assist the cooling of the lithium battery in the high-temperature environment, so as to ensure that the battery meets the condition of performing the pre-cycle treatment.
In the three-time pre-circulation treatment, because of the intercalation and the intercalation of lithium ions, a certain gap exists between the positive electrode plate and the negative electrode plate of the battery and the diaphragm, and free electrolyte can fully contact with the electrode plate so as to improve the infiltration effect of the electrode plate and form a stable SEI film, thereby ensuring the capacity and the service life of the battery.
When the pretreatment and the circulation treatment are carried out, the current multiplying power is from small to large, when the large current multiplying power is adopted, the double-electron reaction is easier to occur, namely, two electrons participate simultaneously to react, the organic lithium salt component is correspondingly easier to generate, at the moment, SEI film molecules are more easily stacked in disorder, the structure is more loose, and the irreversible reaction is more. The loose SEI film can infiltrate more electrolyte, and the ionic conductivity is high; the SEI film crystal nucleus forming speed is high. When the small current multiplying power is formed, single-electron reaction is easier to occur, namely, the reaction can occur only by one electron, the inorganic lithium salt component is correspondingly easier to generate, and at the moment, SEI film molecules are easier to be accumulated orderly, the structure is more compact, and the irreversible reaction is less. The larger the charge current rate, the corresponding increase in battery polarization. Multi-step charging: the current is first reduced and then gradually increased. The stepped multiplying power current formation can not only reduce the polarization level of the battery and improve the charging capacity, but also effectively reduce the charging time and improve the formation efficiency.
Through three times of pre-circulation treatment, a more stable and uniform SEI film is formed, so that co-embedding of solvent molecules can be effectively prevented, damage to electrode materials caused by co-embedding of the solvent molecules is avoided, and the cycle performance and the service life of the battery are greatly improved. Meanwhile, the positive and negative plates can absorb more electrolyte in the circulation process, the medium in the lithium ion deintercalation process in the later period of circulation is increased, the circulation service life of the battery is greatly prolonged, and meanwhile, the positive and negative plates absorb the electrolyte more fully, and the consistency of the performances such as the capacity and the internal resistance of the battery is improved.
From the above, it can be seen that, if the minimum value is adopted in all the time length numerical intervals in each step during the formation, the man-hours for performing the primary pre-cycle, the secondary pre-cycle and the tertiary pre-cycle are 378min, 623min and 868min respectively; if the maximum value is adopted in all duration numerical intervals, the working hours for performing the primary pre-cycle, the secondary pre-cycle and the tertiary pre-cycle are 500min, 810min and 1120imn respectively.
The total duration interval is between 7 hours and 20 hours, so that the formation efficiency of the battery is remarkably improved.
The following are examples of the invention:
embodiment one:
s1, performing pretreatment under the conditions that the pressure is 80KPa and the temperature is 45 ℃, wherein the pretreatment comprises the following steps:
standing for 1min, performing primary charging for 5min, wherein the charging current multiplying power is 0.2 ℃, the cut-off voltage is 3.65V, and the cut-off current is 0.05 ℃;
standing for 1min, performing preforming discharge for 5min, wherein the discharge current multiplying power is 0.5C, and the cut-off voltage is 2.5V;
standing for 1min, and charging for 60min for the second time, wherein the charging current multiplying power is 0.5C and the cut-off current is 0.05C.
S2, performing pre-circulation treatment under the conditions that the temperature is 25 ℃ and the pressure is-30 KPa, wherein the pre-circulation treatment comprises:
pre-circulating charging, wherein the duration is 120min, the charging current multiplying power is 0.2C, and the cut-off current multiplying power is 0.05C;
pre-circulating and standing for 5min until the temperature of the battery is reduced to 25 ℃;
pre-circulating discharge for 120min;
s3, ending charging is carried out for 60min, the charging current multiplying power is 0.5C, and the cut-off current multiplying power is 0.05C.
Embodiment two:
the difference between the present embodiment and the first embodiment is that after the step S2 is repeatedly performed twice, the step S3 is performed again;
embodiment III:
the difference between the present embodiment and the first embodiment is that after the step S2 is repeatedly performed three times, the step S3 is performed again;
embodiment four:
the difference between the present embodiment and the first embodiment is that the maximum value is adopted for each electrostatic and charge-discharge duration.
S1, performing pretreatment under the conditions that the pressure is 80KPa and the temperature is 45 ℃, wherein the pretreatment comprises the following steps:
standing for 10min, performing primary charging for 10min, wherein the charging current multiplying power is 0.2 ℃, the cut-off voltage is 3.65V, and the cut-off current is 0.05 ℃;
standing for 10min, performing preforming discharge for 10min, wherein the discharge current multiplying power is 0.5C, and the cut-off voltage is 2.5V;
standing for 10min, and performing secondary charging for 80min, wherein the charging current multiplying power is 0.5C and the cut-off current is 0.05C.
S2, performing pre-circulation treatment under the conditions that the temperature is 25 ℃ and the pressure is-30 KPa, wherein the pre-circulation treatment comprises:
pre-circulating charging, wherein the duration is 150min, the charging current multiplying power is 0.2C, and the cut-off current multiplying power is 0.05C;
pre-circulating and standing for 10min until the temperature of the battery is reduced to 25 ℃;
pre-circulating discharge for 150min;
s3, ending charging is carried out for 60min, the charging current multiplying power is 0.5C, and the cut-off current multiplying power is 0.05C.
Fifth embodiment:
the difference between the present embodiment and the fourth embodiment is that after the step S2 is repeated twice, the step S3 is performed again.
Example six:
the difference between the present embodiment and the fourth embodiment is that after the step S2 is repeatedly performed three times, the step S3 is performed again.
Comparative example one:
the present comparative example differs from the first example in that only the pre-formation step S1 was performed, the pre-cycle treatment was not performed, the present comparative example was performed three times, and the average value of the test results was taken.
Comparative example two:
the present comparative example differs from example one in that in step S2, the temperature condition of the pre-cycle is 20 ℃.
Comparative example three:
the difference between this comparative example and the first embodiment is that in step S2, the pre-cycle pressure condition is-10 KPa.
Comparative example four:
the present comparative example differs from example one in that in step S2, the temperature condition of the pre-cycle is 22 ℃.
Comparative example five:
the present comparative example differs from example one in that in step S2, the temperature condition of the pre-cycle is 28 ℃.
The test results are measured for a 4680 cylindrical lithium iron phosphate system battery after 8000 cycles at a rated power of 0.5c charge and discharge.
The test results show that after the battery is subjected to the pre-formation treatment and then the pre-circulation treatment, no matter the formation time interval adopts the maximum value or the formation time interval adopts the minimum value, the battery meets the requirement that the capacity retention rate is more than 80% after 8000 times of circulation, and the battery is also a qualified line of the battery.
In the first comparative example, the battery is only subjected to the pretreatment, but not subjected to the pretreatment, the capacity retention rate is 76.9%, the qualification standard of the battery is not met, the second comparative example and the third comparative example are changed according to the temperature condition and the negative pressure condition of the pretreatment, the capacity retention rate is 78.2% and 77%, the cyclic capacity retention rate of the battery can be influenced after the temperature condition and the negative pressure condition exceed the interval, and the capacity retention rate of the battery also meets the standard requirement under the treatment condition of selecting and circulating the temperature of 22 ℃ and 28 ℃ in the end value examples of the temperature interval values of the fifth comparative example and the fifth comparative example.
In conclusion, the hard shell lithium ion battery formation method can ensure that the battery capacity is qualified, greatly reduces the time required by formation, remarkably improves the formation efficiency and has important significance for lithium battery production.
The foregoing description of the preferred embodiments of the invention is not intended to be limiting, but rather is intended to cover all modifications, equivalents, alternatives, and improvements that fall within the spirit and scope of the invention.
Claims (10)
1. A method for forming a hard shell lithium ion battery, comprising the steps of:
s1, after the battery is injected, performing pre-formation treatment under the conditions that the pressure is-70 to-90 KPa and the temperature is 42-48 ℃, and forming the battery into an activated state by means of charging, standing and discharging for 70-150 min;
s2, performing pre-circulation treatment under the conditions that the temperature is 22-28 ℃ and the pressure is in a negative pressure state, wherein the pre-circulation treatment comprises:
pre-circulating charging, wherein the duration is 120-150 min, the charging current multiplying power is 0.2C, and the cut-off current multiplying power is 0.05C;
pre-circulating and standing until the temperature of the battery is reduced to 22-28 ℃;
pre-circulating discharge, wherein the duration is 120-150 min, the discharge current multiplying power is 0.2C, and the cut-off voltage is 2.5V;
s3, ending charging is carried out for 60min, the charging current multiplying power is 0.5C, and the cut-off current multiplying power is 0.05C.
2. The method of forming a hard shell lithium ion battery of claim 1, wherein: the negative pressure condition of the pre-circulation treatment is-20 to-40 KPa.
3. The method of forming a hard shell lithium ion battery of claim 1, wherein: the temperature of the pre-cycling treatment was 25 ℃.
4. The method of forming a hard shell lithium ion battery of claim 1, wherein: the pre-circulation standing time is 5-10 min.
5. The method of forming a hard shell lithium ion battery of any of claims 1-4, wherein: in the step 2, the number of cycles of the pre-cycle treatment is at least three.
6. The method of forming a hard shell lithium ion battery of claim 1, wherein: the pre-formation treatment comprises at least two charging, one discharging and three standing;
the processing steps are as follows: first standing, first charging, second standing, pre-formation discharging, third standing and second charging.
7. The method of forming a hard shell lithium ion battery of claim 6, wherein: the duration of single standing is 1-10 min.
8. The method of forming a hard shell lithium ion battery of claim 6, wherein: the duration of the first charging is 5-10 min, the charging current multiplying power is 0.2 ℃, the cut-off voltage is 3.65V, and the cut-off current is 0.05 ℃.
9. The method of forming a hard shell lithium ion battery of claim 6, wherein: the duration of the pre-formation discharge is 5-10 min, the discharge current multiplying power is 0.5C, and the cut-off voltage is 2.5V.
10. The method of forming a hard shell lithium ion battery of claim 6, wherein: the duration of the second charging is 60-80 min, the charging current multiplying power is 0.5C, and the cut-off current is 0.05C.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311057076.3A CN116885317A (en) | 2023-08-22 | 2023-08-22 | Formation method of hard shell lithium ion battery |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311057076.3A CN116885317A (en) | 2023-08-22 | 2023-08-22 | Formation method of hard shell lithium ion battery |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN116885317A true CN116885317A (en) | 2023-10-13 |
Family
ID=88270189
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202311057076.3A Pending CN116885317A (en) | 2023-08-22 | 2023-08-22 | Formation method of hard shell lithium ion battery |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN116885317A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117996215A (en) * | 2024-04-07 | 2024-05-07 | 宁德时代新能源科技股份有限公司 | Battery, preparation method thereof and electricity utilization device |
-
2023
- 2023-08-22 CN CN202311057076.3A patent/CN116885317A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117996215A (en) * | 2024-04-07 | 2024-05-07 | 宁德时代新能源科技股份有限公司 | Battery, preparation method thereof and electricity utilization device |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| WO2021218814A1 (en) | Battery, apparatus, battery production method, and device | |
| CN101894968B (en) | Novel battery module | |
| CN102694158A (en) | Silicon-containing lithium cathode, preparation method thereof and lithium sulfur battery with silicon-containing lithium cathode | |
| CN116885317A (en) | Formation method of hard shell lithium ion battery | |
| CN105428741A (en) | Charging method for lithium-ion battery | |
| CN111384456A (en) | Pre-charging formation method of lithium ion battery and lithium ion battery | |
| CN111934019A (en) | Rapid formation method of power soft-package polymer lithium ion battery | |
| CN102227031A (en) | Lithium ion battery with high-rate discharge characteristic | |
| WO2024198571A1 (en) | Secondary battery charging method | |
| Zheng et al. | Influence of charge rate on the cycling degradation of LiFePO 4/mesocarbon microbead batteries under low temperature | |
| WO2019114433A1 (en) | Lead-carbon start/stop storage battery for automobile | |
| WO2022067485A1 (en) | Battery charging method and device, and storage medium | |
| CN110994056B (en) | Formation activation process for high-capacity lithium iron phosphate battery | |
| CN115498287B (en) | Pre-embedded lithium graphite negative electrode plate and preparation method and application thereof | |
| CN113991197B (en) | Lithium ion battery and charging method thereof | |
| CN111261962A (en) | Operation and maintenance method of power type lithium iron phosphate battery | |
| CN114883531A (en) | Three-electrode lithium ion battery and lithium pre-charging and lithium supplementing method thereof | |
| CN114865058A (en) | Preparation method of silicon-based soft package lithium ion battery | |
| CN114122356A (en) | Modified hard carbon negative electrode material with improved performance and preparation method thereof | |
| Yu et al. | The influence of coupling of charge/discharge rate and short term cycle on the battery capacity of Li-ion batteries | |
| Yu et al. | Research on energy storage technology of lead-acid battery based on “reduction and resource utilization” | |
| KR20040110331A (en) | Method of post-treating for rechargeable lithium battery | |
| CN109768220A (en) | A method of reducing lithium ion battery self discharge | |
| CN116995318B (en) | 3.2V formation process of lithium iron phosphate battery | |
| CN115275105B (en) | Silicon-based negative electrode plate, secondary battery and power utilization device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |