CN112946505B - Method for rapidly testing cycle life of lithium ion battery - Google Patents
Method for rapidly testing cycle life of lithium ion battery Download PDFInfo
- Publication number
- CN112946505B CN112946505B CN201911268271.4A CN201911268271A CN112946505B CN 112946505 B CN112946505 B CN 112946505B CN 201911268271 A CN201911268271 A CN 201911268271A CN 112946505 B CN112946505 B CN 112946505B
- Authority
- CN
- China
- Prior art keywords
- charging
- lithium ion
- ion battery
- voltage
- discharge
- 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.)
- Active
Links
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/36—Arrangements for testing, measuring or monitoring the electrical condition of accumulators or electric batteries, e.g. capacity or state of charge [SoC]
- G01R31/392—Determining battery ageing or deterioration, e.g. state of health
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/36—Arrangements for testing, measuring or monitoring the electrical condition of accumulators or electric batteries, e.g. capacity or state of charge [SoC]
- G01R31/378—Arrangements for testing, measuring or monitoring the electrical condition of accumulators or electric batteries, e.g. capacity or state of charge [SoC] specially adapted for the type of battery or accumulator
-
- 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 method for rapidly testing the cycle life of a lithium ion battery, which is characterized in that the charging current when the battery is in a low SOC (state of charge) state is reduced, so that an SEI (solid electrolyte interface) film newly formed in each charging process is more compact, and the reaction consumption of available lithium ions in the battery is accelerated; meanwhile, by improving the charge cut-off voltage of the battery, the consumption of lithium ion reaction, the decline of electrode materials and the decomposition of electrolyte are accelerated; the high-temperature intermittent circulating long-time standing step is replaced by a constant-voltage charging step or partially replaced by the high-temperature intermittent circulating long-time standing step, so that various side reactions in the battery can be accelerated, the cycle life of the lithium ion battery can be rapidly tested, and further, small nested circulation is added under the charging system, so that the attenuation of the battery can be accelerated more rapidly; the rapid test method can realize the test rate of high-temperature intermittent circulation on the premise of ensuring the consistency of the battery capacity attenuation mechanism, greatly shortens the time required by the test, and is beneficial to the rapid development of battery products.
Description
Technical Field
The invention belongs to the technical field of battery testing methods, and particularly relates to a method for rapidly testing the cycle life of a lithium ion battery.
Background
Lithium ion batteries have been widely used in consumer electronics and electric vehicle products due to their high energy density, long cycle life, no memory effect, and the like. Consumer electronics, particularly notebook computers, require batteries that still have good cycling and storage properties at higher temperatures. The end manufacturer requires that the battery pass some specific high temperature tests to simulate some of the actual operating conditions of the battery.
The current battery high-temperature performance test scheme is high-temperature intermittent circulation, and comprises the following specific steps: the method comprises the steps of completely discharging a fully charged battery at high temperature, standing for a short time (short standing time between known normal discharge and charge specified by a terminal manufacturer, the standing process is not particularly emphasized below), completely charging at constant current and constant voltage, and standing for a long time, wherein the steps are sequentially recorded as a cycle, the long standing time is longer than the short standing time, and the test standard requires that the capacity retention rate of the battery after the battery is circulated for a certain number of times according to the steps is not lower than a specific value. The high temperature intermittent cycle test takes a long time and is carried out according to the general standard, and the total cycle time is generally more than 100 days. The long test period is very disadvantageous to the rapid development and optimization of the battery product, and therefore, it is necessary to develop a corresponding accelerated test scheme.
The working life of the lithium ion battery needs to be evaluated through various circulation systems, and the problem of long test period exists in any circulation test. Aiming at the problem that the cycle test of the lithium ion battery consumes too long time, the prior art discloses a method for testing the service life of the battery in an accelerated manner, the battery is subjected to floating charge with time increment after constant current charge under the high-temperature condition until the discharge capacity at the room temperature is lower than the nominal capacity by 75%, a conversion table of the normal-temperature service life and the high-temperature service life, which is tested in advance and manufactured, is inquired, and the cycle service life of the battery under the normal-temperature condition is estimated. Although the above scheme can achieve the effect of accelerated test of the battery life, the following disadvantages exist: firstly, the high-temperature cycle life and the normal-temperature cycle life are only corresponding through the normal-temperature discharge capacity, which is not enough to ensure that the attenuation mechanism of the battery capacity is consistent, but the accelerated test scheme with inconsistent attenuation mechanism cannot be regarded as an effective scheme. Second, although the normal temperature cycle life and the normal high temperature cycle life can be tested in advance and made into a life data conversion table, since the consistency of the capacity fading mechanism cannot be guaranteed, for each battery made of a new material and a new scheme, a large amount of time is required to make the life data conversion table, and it is actually difficult to really achieve the effect of accelerating the test.
Disclosure of Invention
In order to overcome the defects in the prior art, the invention aims to provide a method for rapidly testing the cycle life of a lithium ion battery, which can well solve the problem that the cycle life test of the lithium ion battery takes too long. The method mainly reduces the charging current when the battery is in a low SOC state, so that an SEI film newly formed in each charging process is more compact, and the reaction consumption of available lithium ions in the battery is accelerated; meanwhile, by increasing the charge cut-off voltage of the battery, the reaction consumption of lithium ions, the decline of electrode materials and the decomposition of electrolyte are accelerated; the long-time standing step of high-temperature intermittent circulation is replaced or partially replaced by a constant-voltage charging step, and small nested circulation is added under the charging system, so that the battery attenuation can be accelerated more quickly; the rapid test of high-temperature intermittent circulation is realized on the premise of ensuring the consistency of the battery capacity attenuation mechanism, the time required by the test is greatly shortened, and the rapid development of battery products is facilitated.
The invention aims to realize the following technical scheme:
a method of rapidly testing the cycle life of a lithium ion battery, the method comprising:
(1) The method comprises the following steps of carrying out discharge treatment on the lithium ion battery, and also comprising a discharge standing step after the discharge is finished;
(2) Carrying out constant current charging on the lithium ion battery after the lithium ion battery is discharged and kept still under a low-rate condition, and carrying out constant current charging under the low-rate condition until the design capacity of the lithium ion battery is less than or equal to 80%;
(3) The lithium ion battery in the step (2) is subjected to constant current under the known rate conditionCharging by current, and charging by constant current to charging upper limit voltage U under known multiplying power Upper part of Said upper limit charging voltage U On the upper part Greater than the known upper limit charging voltage Ug On the upper part ；
(4) Repeating the step (1), the step (2) and the step (3) at least 1 time;
(5) Performing constant voltage charging on the lithium ion battery in the step (4), optionally, further comprising a charging standing step in the constant voltage charging process, wherein the voltage of the constant voltage charging is charging upper limit voltage U On the upper part ；
(6) The lithium ion battery is circulated once according to the steps (1) to (5); when the charge-discharge cycle time of the lithium ion battery reaches a threshold value, recording the high-temperature capacity retention rate of the lithium ion battery;
or when the high-temperature capacity retention rate of the lithium ion battery reaches a threshold value, recording the charge-discharge cycle time used by the lithium ion battery, namely realizing the rapid test of the cycle life of the lithium ion battery.
According to the invention, the method is carried out by placing the lithium ion battery in an environment above 40 ℃.
According to the invention, in the step (1), the discharge treatment may be, for example, a discharge treatment of discharging the lithium ion battery at a discharge rate of 0.2-6C to a discharge lower limit voltage U Lower part ’。
In the step (1), the known discharge lower limit voltage Ug Lower part And discharge lower limit voltage U Lower part ' satisfies the following relation: 1V is not less than Ug Lower part ’-U Lower part ’≥0V。
In step (1), the known discharge lower limit voltage Ug Lower part ' is 2.0-3.6V.
According to the invention, in the step (1), the discharge standing time is 1-60min.
According to the invention, in the step (2), the low rate is smaller than the rate of the known constant current charging, and the rate of the known constant current charging refers to the rate adopted in the constant current charging process in the charging step of the battery specified by the terminal manufacturer in the conventional high-temperature intermittent circulation.
In the step (2), the low multiplying power is smaller than the multiplying power of the known constant current charging, for example, the low multiplying power is smaller than the multiplying power of the known constant current charging by more than 0.1C;
in the step (2), the low magnification is, for example, 0.1 to 0.6C;
in the step (2), the design capacity of the lithium ion battery is 2000-8000mAh, such as 4000mAh;
according to the invention, in the step (2), in each cycle process, the low-magnification conditions can be the same or different; in different circulation processes, the low-magnification conditions can be the same or different;
according to the invention, in the step (3), the lithium ion battery is subjected to constant current charging under the condition of a known multiplying power, and the lithium ion battery is subjected to constant current charging to the charging upper limit voltage U under the condition of the known multiplying power On the upper part 。
In the step (3), the charging upper limit voltage U On the upper part And a known upper limit charging voltage Ug On the upper part Satisfies the following relation: 1V is more than or equal to U Upper part of -Ug On the upper part >0V。
In the step (3), the known charging upper limit voltage Ug On the upper part Is the upper limit voltage of charge used in the charging step of the battery high-temperature intermittent cycle specified by the terminal manufacturer.
In the step (3), the known charging upper limit voltage Ug On the upper part For example, it may be 3.6-4.5V.
According to the invention, in step (4), step (1), step (2) and step (3) are repeated at least 1 to 10 times, for example 2 to 6 times;
in the step (4), the step (1), the step (2) and the step (3) in each circulation process may be the same or different.
According to the invention, in the step (5), the time of constant voltage charging is longer than the discharging standing time of the step (1).
In the step (5), the longer the number of cycles of the step (4), the longer the constant voltage charging time, for example, the constant voltage charging time is 1 to 100 hours.
According to the present invention, in step (5), the time of the constant voltage charging process is the same or different, and for example, in each cycle, the time of the discharging process in step (1), the time of the discharging standing process, the time of the constant current charging in step (2), and the time of the constant current charging in step (3) may be different, and therefore, the time of the constant voltage charging may be different in each cycle.
The invention has the beneficial effects that:
the invention provides a method for rapidly testing the cycle life of a lithium ion battery, which is characterized in that the charging current when the battery is in a low SOC (state of charge) state is reduced, so that an SEI (solid electrolyte interface) film newly formed in each charging process is more compact, and the reaction consumption of available lithium ions in the battery is accelerated; meanwhile, by improving the charge cut-off voltage of the battery, the consumption of lithium ion reaction, the decline of electrode materials and the decomposition of electrolyte are accelerated; the long-time standing step of high-temperature intermittent circulation replaces or partially replaces the long-time standing of the high-temperature intermittent circulation with the constant-voltage charging step, so that various side reactions in the battery can be accelerated, the cycle life of the lithium ion battery can be rapidly tested, and further small nested circulation is added under the charging system, so that the battery attenuation can be accelerated more rapidly; the rapid test method can realize the test rate of high-temperature intermittent circulation on the premise of ensuring the consistency of the battery capacity attenuation mechanism, greatly shortens the time required by the test, and is beneficial to the rapid development of battery products.
Drawings
Fig. 1 is a schematic flow chart of a method for rapidly testing cycle life of a lithium ion battery according to the present invention.
Detailed Description
As described above, the present invention provides a method for rapidly testing cycle life of a lithium ion battery, the method comprising:
(1) The method comprises the following steps of carrying out discharge treatment on the lithium ion battery, and also comprising a discharge standing step after the discharge is finished;
(2) Carrying out constant current charging on the lithium ion battery after the lithium ion battery is discharged and kept still under a low-rate condition, and carrying out constant current charging under the low-rate condition until the design capacity of the lithium ion battery is less than or equal to 80%;
(3) And (3) carrying out constant current charging on the lithium ion battery in the step (2) under the known multiplying power condition, and carrying out constant current charging to charging under the known multiplying powerElectrical upper limit voltage U On the upper part The charging upper limit voltage U On the upper part Greater than the known upper limit charging voltage Ug On the upper part ；
(4) Repeating the step (1), the step (2) and the step (3) for at least 1 time;
(5) Performing constant voltage charging on the lithium ion battery in the step (4), optionally, further comprising a charging standing step in the constant voltage charging process, wherein the voltage of the constant voltage charging is charging upper limit voltage U On the upper part ；
(6) The lithium ion battery is circulated once according to the steps (1) to (5); when the charge-discharge cycle time of the lithium ion battery reaches a threshold value, recording the high-temperature capacity retention rate of the lithium ion battery;
or when the high-temperature capacity retention rate of the lithium ion battery reaches a threshold value, recording the charge-discharge cycle time used by the lithium ion battery, namely realizing the rapid test of the cycle life of the lithium ion battery.
In one embodiment of the invention, the method is carried out by subjecting the lithium ion battery to an environment having an elevated temperature (e.g., above 40 ℃, e.g., 40-55 ℃, e.g., 45 ℃).
In one aspect of the present invention, in step (1), the electric discharge treatment may be, for example, an electric discharge step treatment in a high-temperature intermittent cycle process known in the art.
Illustratively, the discharge treatment may be, for example, a discharge treatment of the lithium ion battery at a discharge rate of 0.2 to 6C (e.g., 0.2C, 0.5C, 0.8C, 1C, 1.5C, 2C, 2.5C, 3C, 4C, 5C, or 6C) and discharging to a discharge lower limit voltage U Lower part ’。
In one embodiment of the invention, in step (1), the known lower limit discharge voltage Ug Lower part And discharge lower limit voltage U Lower part ' satisfies the following relation: 1V is not less than Ug Lower part ’-U Lower part ’≥0V。
In one embodiment of the present invention, in step (1), the known discharge lower limit voltage Ug Lower part ' is a discharge lower limit voltage used in a discharge step of a high-temperature intermittent cycle of the battery specified by the terminal manufacturer.
In one embodiment of the present invention, in step (1)Said known lower limit voltage of discharge Ug Lower part ' is 2.0-3.6V.
In one embodiment of the present invention, in the step (1), the discharge is allowed to stand for 1 to 60min.
In one aspect of the present invention, in step (2), the low rate is smaller than the rate of known constant current charging, and the rate of known constant current charging refers to the rate adopted in the constant current charging process in the charging step of the conventional high-temperature intermittent cycle of the battery specified by the terminal manufacturer. Illustratively, the known constant current charging rate is, for example, 0.65-0.8C, for example, 0.7C.
In one embodiment of the present invention, in step (2), the low rate is smaller than the rate of the known constant current charging, for example, the low rate is smaller than the rate of the known constant current charging by 0.1C or more, for example, smaller than 0.1C, 0.2C, 0.3C, 0.4C, 0.5C, or 0.6C.
In one embodiment of the present invention, in the step (2), the low magnification is, for example, 0.1 to 0.6C, for example, 0.1C, 0.2C, 0.3C, 0.4C, 0.5C, or 0.6C.
In one embodiment of the present invention, in the step (2), the designed capacity of the lithium ion battery is not particularly limited, and may be, for example, 2000 to 8000mAh, for example 4000mAh.
In one embodiment of the present invention, in step (2), when the capacity of the lithium ion battery is less than or equal to 80% of the designed capacity of the lithium ion battery, the battery is charged with a current less than the rate of the known constant current charging, i.e., a low rate, which is mainly set for the purpose of reducing the charging current when the battery is at a low SOC, so that the newly formed SEI film in each charging process can be denser, and the reactive consumption of the available lithium ions in the battery can be accelerated.
In one embodiment of the present invention, in step (2), in each cycle, the low-magnification conditions may be the same or different;
for example, the lithium ion battery is first charged to 80% of its designed capacity with 0.1C and then charged to 4.4V with 0.7C.
Also for example, first, the battery is charged with 0.1C to 40% of the designed capacity of the lithium ion battery, then charged with 0.3C to 70% of the designed capacity of the lithium ion battery, and then charged with 0.7C to 4.4V.
In one embodiment of the present invention, in step (2), in different recycling processes, the low-magnification conditions may be the same or different;
for example, the operation is repeated a plurality of times by first charging to 80% of the designed capacity of the lithium ion battery with 0.1C and then charging to 4.4V with 0.7C.
For example, the first 10 times of the cycle charging process of the lithium ion battery is firstly charged to 50% of the designed capacity of the lithium ion battery by using 0.1C and then charged to 4.38V by using 0.7C, and then the cycle is changed to be charged to 30% of the designed capacity of the lithium ion battery by using 0.2C and then charged to 4.36V by using 0.7C.
In one scheme of the invention, in the step (3), the lithium ion battery is subjected to constant current charging under the condition of a known multiplying power, and the lithium ion battery is subjected to constant current charging to the charging upper limit voltage U under the condition of the known multiplying power On the upper part 。
In one embodiment of the present invention, in the step (3), the charging upper limit voltage U is adjusted Upper part of Greater than the known upper limit charging voltage Ug On the upper part The purpose of the method is that the consumption of lithium ion reaction, the decline of electrode materials and the decomposition of electrolyte can be accelerated in the adjusted charging process, and a guarantee is provided for realizing the rapid test of the cycle life of the lithium ion battery.
In one embodiment of the present invention, in the step (3), the charging upper limit voltage U Upper part of And the known charging upper limit voltage Ug On the upper part Satisfies the following relation: 1V is more than or equal to U On the upper part -Ug On the upper part >0V。
In one aspect of the present invention, in the step (3), the known upper limit charging voltage Ug On the upper part Is the upper limit voltage of charge used in the charging step of the battery high-temperature intermittent cycle specified by the terminal manufacturer.
In one aspect of the present invention, in the step (3), the known upper limit charging voltage Ug On the upper part For example, it may be 3.6-4.5V.
In one embodiment of the present invention, in step (4), step (1), step (2) and step (3) are repeated at least 1 to 10 times, for example, 2 to 6 times.
In one embodiment of the present invention, in step (4), step (1), step (2), and step (3) in each cycle may be the same or different.
In one aspect of the present invention, in the step (5), the constant voltage charging is the charging upper limit voltage U in the step (3) Upper part of Charging is carried out; various side reactions in the battery can be accelerated in the constant-voltage charging process, and the rapid test of the cycle life of the lithium ion battery is realized.
In one aspect of the present invention, in the step (5), the time of the constant voltage charging is longer than the discharging rest time of the step (1).
In one aspect of the present invention, in the step (5), the larger the number of cycles of the step (4), the longer the constant voltage charging time, for example, the constant voltage charging time is 1 to 100 hours.
In one embodiment of the present invention, in the step (5), the time of the charging standing step is not particularly limited, and may be, for example, zero or any other time, but it is sufficient to ensure that the time of the constant voltage charging is longer than the time of the discharging standing step in the step (1).
In one aspect of the present invention, in the step (5), the constant voltage charging process may be continuously performed for a long time, or may be combined with the charging and standing step; for example, constant voltage charging may be continued, or at least one charging rest step may be provided during constant voltage charging, and the time of each charging rest step is not particularly limited, but the time of constant voltage charging is ensured to be longer than that of the discharging rest step of step (1). That is, in the constant voltage charging process, at least one charging stand step may be included, or the charging stand step may not be included. For example, after constant voltage charging for a period of time, a charging standing step is performed, then constant voltage charging is performed, then a charging standing step is performed, and so on, and a plurality of such operations are repeated until the cycle is completed.
In one aspect of the present invention, in the step (5), the time of the constant voltage charging process is the same or different, and for example, during each cycle, the time of the discharging process in the step (1), the time of the discharging standing process, the time of the constant current charging in the step (2), and the time of the constant current charging in the step (3) may be different, and thus, during each cycle, the time of the constant voltage charging may be different.
In one scheme of the invention, in the step (6), in each cycle process, the operations of the step (1), the step (2), the step (3), the step (4) and the step (5) are the same or different; for example, the discharging process of step (1), the constant current charging rate of step (2), and the charging upper limit voltage U of step (3) during each cycle On the upper part The number of cycles of step (4) and the time of constant voltage charging in step (5) may be the same or different.
The preparation method of the present invention will be described in further detail with reference to specific examples. It is to be understood that the following examples are only illustrative and explanatory of the present invention and should not be construed as limiting the scope of the present invention. All the technologies realized based on the above-mentioned contents of the present invention are covered in the protection scope of the present invention.
The experimental methods used in the following examples are all conventional methods unless otherwise specified; reagents, materials and the like used in the following examples are commercially available unless otherwise specified.
Example 1
The lithium ion battery is manufactured according to the conventional manufacturing process, the positive active material is lithium cobaltate, the negative active material is graphite, and the design capacity of the battery is 4000mAh. The known upper charge limit voltage of the lithium ion battery is 4.35V, the known lower discharge limit voltage is 3.0V, and the known charge rate is 0.7C.
The lithium ion battery is placed in an environment of 45 ℃, and the test process is as follows:
carrying out discharge treatment on the fully charged lithium ion battery, wherein the discharge process is to discharge to 3.0V by adopting 0.5C, and then discharging and standing for 10min;
the discharged lithium ion battery is charged by firstly charging to 80% of the designed capacity at 0.1C, then charging to 4.38V at 0.7C multiplying power, performing the charge-discharge cycle for 6 times, then performing constant-voltage charging for 100 hours at 4.38V, starting the discharging step after the constant voltage is finished to perform nested cycle, and recording the corresponding cycle time when the capacity retention rate reaches 90%, wherein the results are shown in table 1.
Example 2
The lithium ion battery was the same as in example 1, and the test method was different from that in example 1.
The test method of this example is as follows:
the lithium ion battery is placed in an environment at 50 ℃, and the test process is as follows:
carrying out discharge treatment on the fully charged lithium ion battery, wherein the discharge process is to discharge to 3.0V by adopting 0.5C, and then discharging and standing for 30min;
and (2) performing charging treatment on the discharged lithium ion battery, namely firstly charging to 40% of the designed capacity by adopting 0.1C, then charging to 70% of the designed capacity by adopting 0.3C, then charging to 4.4V by adopting 0.7C, performing charging and discharging circulation for 3 times, then starting constant-voltage charging for 30 hours at 4.4V, standing for 20 hours, entering a discharging step for nested circulation after the test is finished, and recording the corresponding circulation time when the capacity retention rate reaches 90%, wherein the results are shown in table 1.
Example 3
The lithium ion battery was the same as in example 1, and the test method was different from that in example 1.
The test method of this example is as follows:
the lithium ion battery is placed in an environment of 45 ℃, and the test process is as follows:
performing discharge treatment on the fully charged lithium ion battery, wherein the discharge process is to discharge to 3.8V at 1C, discharge to 2.8V at 0.5C, and then perform discharge standing for 60min;
and (2) performing charging treatment on the discharged lithium ion battery, firstly charging to 60% of the designed capacity by adopting 0.1C, then charging to 4.4V at the multiplying power of 0.7C, performing 5 times of charging and discharging circulation, then performing constant-voltage charging for 80 hours at 4.4V, entering a discharging step to perform nested circulation after the test is completed, and recording the corresponding circulation time when the capacity retention rate reaches 90%, wherein the results are shown in table 1.
Example 4
The lithium ion battery was the same as in example 1, and the test method was different from that in example 1.
The test method of this example is as follows:
the lithium ion battery is placed in an environment of 50 ℃, and the test process is as follows:
carrying out discharge treatment on the fully charged lithium ion battery, wherein the discharge process is to discharge to 3.0V by adopting 0.5C, and then discharging and standing for 1min;
and (3) performing charging treatment on the discharged lithium ion battery, firstly charging to 30% of the designed capacity by adopting 0.1C, then charging to 4.4V by adopting 0.7C, performing the charging and discharging cycle for 3 times, then starting to perform constant-voltage charging for 60 hours at 4.4V, entering a discharging step to perform nested cycle after the test is completed, and recording the corresponding cycle time when the capacity retention rate reaches 90%, wherein the results are shown in Table 1.
Example 5
The lithium ion battery was the same as in example 1, and the test method was different from that in example 1.
The test method of this example is as follows:
the lithium ion battery is placed in an environment with the temperature of 55 ℃, and the test process is as follows:
performing discharge treatment on the fully charged lithium ion battery, wherein the discharge process is to discharge to 3.0V at 0.5C, then discharge to 2.6V at 0.1C, and then perform discharge standing for 1min;
and (2) performing charging treatment on the discharged lithium ion battery, firstly charging to 40% of the designed capacity by adopting 0.2C, then charging to 4.42V by adopting 1C, performing the charging and discharging cycle for 2 times, then starting constant-voltage charging for 30 hours at 4.42V, standing for 8 hours, entering a discharging step for nested cycle after the test is completed, and recording the corresponding cycle time when the capacity retention rate reaches 90%, wherein the results are shown in Table 1.
Example 6
The lithium ion battery was the same as in example 1, and the test method was different from that in example 1.
The test method of this example is as follows:
the lithium ion battery is placed in an environment of 45 ℃, and the test process is as follows:
performing discharge treatment on the fully charged lithium ion battery, wherein the discharge process is to discharge to 3.8V at 1C, discharge to 2.0V at 0.7C and then perform discharge standing for 20min;
and (2) performing charging treatment on the discharged lithium ion battery, firstly charging to 60% of the designed capacity by adopting 0.5C, then charging to 4.36V at the multiplying power of 0.7C, performing the charging and discharging cycle for 1 time, then performing constant-voltage charging for 15 hours at the multiplying power of 4.36V, entering a discharging step for nested cycle after the test is completed, and recording the corresponding cycle time when the capacity retention rate reaches 90%, wherein the results are shown in Table 1.
Comparative example 1
The lithium ion battery was the same as in example 1, and the test method was different from that in example 1.
The test method of this comparative example is as follows:
the lithium ion battery is placed in an environment of 45 ℃, and the test process is as follows:
discharging the fully charged lithium ion battery to 3.0V at a discharge rate of 0.5C, and then discharging and standing for 10min;
the discharged lithium ion battery was charged to 4.35V at a rate of 0.7C, and then was subjected to constant voltage charging at a constant voltage of 4.35V, and the time of constant voltage charging was adjusted so that the total time per cycle was 24 hours, and the cycle time corresponding to a capacity retention rate of 90% was recorded, and the results are shown in table 1.
TABLE 1
| Examples/comparative examples | Cycle time at a high-temperature capacity retention of 90% | Capacity at normal temperatureRecovery rate |
| Example 1 | 32 days | 91.9％ |
| Example 2 | 28 days | 90.8％ |
| Example 3 | 30 days | 92.3％ |
| Example 4 | 32 days | 92.0％ |
| Example 5 | 25 days | 91.4％ |
| Example 6 | 35 days | 92.1％ |
| Comparative example 1 | 98 days | 91.7％ |
Table 1 shows the cycle time and the room-temperature capacity recovery rate used when the high-temperature capacity retention rates of the batteries of the examples of the present invention and the comparative examples were the same. The accelerated test scheme greatly shortens the time required by high-temperature intermittent cycle life evaluation, and when the high-temperature capacity retention rate of the accelerated test battery is close to that of the conventional test battery, the normal-temperature capacity recovery rate is also close to that of the conventional test battery, so that the capacity fading mechanism of the accelerated test battery is proved to be not obviously different from that of the conventional test battery.
The embodiments of the present invention have been described above. However, the present invention is not limited to the above embodiment. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (18)
1. A method of rapidly testing the cycle life of a lithium ion battery, the method comprising:
(1) The method comprises the following steps of carrying out discharge treatment on the lithium ion battery, and also comprising a discharge standing step after the discharge is finished;
(2) Carrying out constant current charging on the lithium ion battery after the lithium ion battery is discharged and kept still under the condition of low multiplying power which is less than the multiplying power of the known constant current charging, and carrying out constant current charging under the low multiplying power to be less than or equal to 80% of the design capacity of the lithium ion battery; the multiplying power of the known constant current charging is 0.65-0.8C;
(3) Performing constant current charging on the lithium ion battery in the step (2) under the condition of the known constant current charging multiplying power, and performing constant current charging to the charging upper limit voltage U under the known constant current charging multiplying power On the upper part Said upper limit charging voltage U On the upper part Greater than the known upper limit charging voltage Ug Upper part of (ii) a The known upper limit charging voltage Ug On the upper part 3.6-4.5V;
(4) Repeating the step (1), the step (2) and the step (3) at least 1 time;
(5) Performing constant voltage charging on the lithium ion battery in the step (4), wherein the voltage of the constant voltage charging is charging upper limit voltage U On the upper part ；
(6) The lithium ion battery is in one cycle from the step (1) to the step (5); when the charge-discharge cycle time of the lithium ion battery reaches a threshold value, recording the high-temperature capacity retention rate of the lithium ion battery;
or when the high-temperature capacity retention rate of the lithium ion battery reaches a threshold value, recording the charge-discharge cycle time used by the lithium ion battery, namely realizing the rapid test of the cycle life of the lithium ion battery.
2. The method of claim 1, wherein the method is performed by subjecting the lithium ion battery to an environment above 40 ℃.
3. The method according to claim 1, wherein in the step (1), the discharge treatment is to discharge the lithium ion battery at a discharge rate of 0.2-6C to a discharge lower limit voltage U Lower part ’。
4. The method according to claim 3, wherein in the step (1), the lower limit discharge voltage Ug is known Lower part And discharge lower limit voltage U Lower part ' satisfies the following relation: 1V is not less than Ug Lower part ’-U Lower part ' > 0V, the known discharge lower limit voltage Ug Lower part ' is 2.0-3.6V.
5. The method according to claim 1, wherein in the step (1), the discharge is kept still for 1-60min.
6. The method of claim 1, wherein in step (2), the low rate is less than a known constant current charging rate of 0.1C or greater.
7. The method according to claim 1, wherein in step (2), the low magnification is 0.1-0.6C.
8. The method of claim 1, wherein in step (2), the design capacity size of the lithium ion battery is 2000-8000 mAh.
9. The method of claim 8, wherein in step (2), the design capacity of the lithium ion battery is 4000mAh.
10. The method according to claim 1, wherein in step (2), the low-rate conditions are the same or different during each cycle; the low rate conditions are the same or different during different cycles.
11. The method according to claim 1, wherein in step (3), the charging upper limit voltage U On the upper part And a known upper limit charging voltage Ug On the upper part Satisfies the following relation: 1V is more than or equal to U Upper part of -Ug On the upper part >0V。
12. The method according to claim 1, wherein in step (4), step (1), step (2) and step (3) are repeated 1-10 times.
13. The method of claim 12, wherein in step (4), step (1), step (2) and step (3) are repeated 2-6 times.
14. The method of claim 1, wherein in step (4), step (1), step (2) and step (3) are the same or different during each cycle.
15. The method according to any one of claims 1 to 14, wherein in the step (5), the constant voltage charging process further comprises a charging standing step.
16. The method according to claim 1, wherein in the step (5), the time of the constant voltage charging is longer than the discharging rest time of the step (1).
17. The method as claimed in claim 1, wherein, in the step (5), the constant voltage charging is performed for 1-100 hours.
18. The method according to claim 1, wherein the time of the constant voltage charging process in step (5) is the same or different according to the difference of the time of the discharging process of step (1), the time of the discharging standing process, the time of the constant current charging of step (2), and the time of the constant current charging of step (3) during each cycle.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911268271.4A CN112946505B (en) | 2019-12-11 | 2019-12-11 | Method for rapidly testing cycle life of lithium ion battery |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911268271.4A CN112946505B (en) | 2019-12-11 | 2019-12-11 | Method for rapidly testing cycle life of lithium ion battery |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112946505A CN112946505A (en) | 2021-06-11 |
| CN112946505B true CN112946505B (en) | 2023-03-14 |
Family
ID=76234083
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201911268271.4A Active CN112946505B (en) | 2019-12-11 | 2019-12-11 | Method for rapidly testing cycle life of lithium ion battery |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112946505B (en) |
Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101299059A (en) * | 2007-04-30 | 2008-11-05 | 三星Sdi株式会社 | Method for testing cycle life of rechargeable battery |
| CN103344917A (en) * | 2013-06-13 | 2013-10-09 | 北京交通大学 | Lithium battery cycle life quick testing method |
| CN104297692A (en) * | 2014-10-10 | 2015-01-21 | 长兴杜塞电源有限公司 | Method for detecting service life of battery |
| CN104678319A (en) * | 2015-03-11 | 2015-06-03 | 浙江中科立德新材料有限公司 | Method for simulation cycle test of lithium battery |
| CN105068009A (en) * | 2015-07-14 | 2015-11-18 | 盐城工学院 | Battery cycle life prediction method |
| CN106093794A (en) * | 2016-08-01 | 2016-11-09 | 深圳市电科电源股份有限公司 | The high temperature service life accelerated test method of ferric phosphate lithium cell |
| CN106199444A (en) * | 2016-07-11 | 2016-12-07 | 深圳天珑无线科技有限公司 | The method and system of prediction battery cycle life |
| CN107728072A (en) * | 2017-10-10 | 2018-02-23 | 合肥国轩高科动力能源有限公司 | A kind of method for quick predicting of cycle life of lithium ion battery |
| CN108445414A (en) * | 2018-04-26 | 2018-08-24 | 合肥国轩高科动力能源有限公司 | A kind of method for rapidly testing of ternary cycle life of lithium ion battery |
| CN109061513A (en) * | 2018-09-21 | 2018-12-21 | 合肥国轩高科动力能源有限公司 | A kind of test method improving LiFePO4 dynamic lithium battery cycle life |
| CN109216810A (en) * | 2018-09-07 | 2019-01-15 | 深圳市比克动力电池有限公司 | A kind of method of charging lithium-ion battery and its cycle performance test method |
| CN109596997A (en) * | 2018-11-21 | 2019-04-09 | 湖北锂诺新能源科技有限公司 | Cycle life of lithium ion battery test method |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7518340B2 (en) * | 2005-12-15 | 2009-04-14 | Dell Products L.P. | Method and system for charge rate adjustment to enhance battery cycle life |
| US10122042B2 (en) * | 2017-01-12 | 2018-11-06 | StoreDot Ltd. | Increasing cycling lifetime of fast-charging lithium ion batteries |
-
2019
- 2019-12-11 CN CN201911268271.4A patent/CN112946505B/en active Active
Patent Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101299059A (en) * | 2007-04-30 | 2008-11-05 | 三星Sdi株式会社 | Method for testing cycle life of rechargeable battery |
| CN103344917A (en) * | 2013-06-13 | 2013-10-09 | 北京交通大学 | Lithium battery cycle life quick testing method |
| CN104297692A (en) * | 2014-10-10 | 2015-01-21 | 长兴杜塞电源有限公司 | Method for detecting service life of battery |
| CN104678319A (en) * | 2015-03-11 | 2015-06-03 | 浙江中科立德新材料有限公司 | Method for simulation cycle test of lithium battery |
| CN105068009A (en) * | 2015-07-14 | 2015-11-18 | 盐城工学院 | Battery cycle life prediction method |
| CN106199444A (en) * | 2016-07-11 | 2016-12-07 | 深圳天珑无线科技有限公司 | The method and system of prediction battery cycle life |
| CN106093794A (en) * | 2016-08-01 | 2016-11-09 | 深圳市电科电源股份有限公司 | The high temperature service life accelerated test method of ferric phosphate lithium cell |
| CN107728072A (en) * | 2017-10-10 | 2018-02-23 | 合肥国轩高科动力能源有限公司 | A kind of method for quick predicting of cycle life of lithium ion battery |
| CN108445414A (en) * | 2018-04-26 | 2018-08-24 | 合肥国轩高科动力能源有限公司 | A kind of method for rapidly testing of ternary cycle life of lithium ion battery |
| CN109216810A (en) * | 2018-09-07 | 2019-01-15 | 深圳市比克动力电池有限公司 | A kind of method of charging lithium-ion battery and its cycle performance test method |
| CN109061513A (en) * | 2018-09-21 | 2018-12-21 | 合肥国轩高科动力能源有限公司 | A kind of test method improving LiFePO4 dynamic lithium battery cycle life |
| CN109596997A (en) * | 2018-11-21 | 2019-04-09 | 湖北锂诺新能源科技有限公司 | Cycle life of lithium ion battery test method |
Non-Patent Citations (3)
| Title |
|---|
| Lithium-ion battery aging mechanisms and life model under different charging stresses;Yang Gao et al.;《Journal of Power Source》;20170715;第356卷;第103-114页 * |
| 锂二次电池的高温循环性能及其容量损失;李连兴等;《电源技术》;20091120(第11期);第970-973页 * |
| 锂离子电池加速循环新评估方法研究;曹锦珠等;《安全与电磁兼容》;20141225(第06期);第32-36页 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN112946505A (en) | 2021-06-11 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR101651991B1 (en) | Method and apparatus for fast charging of battery | |
| US10345388B2 (en) | Method for screening lithium ion battery | |
| CN108445414B (en) | Method for rapidly testing cycle life of ternary lithium ion battery | |
| CN103018683A (en) | Battery cycle performance accelerating and evaluating method | |
| CN112689934A (en) | Charging method, electronic device, and storage medium | |
| CN108336435B (en) | Lithium ion battery charging method considering charging energy efficiency | |
| CN108493482B (en) | Lithium ion battery and formation method thereof | |
| You et al. | Charging strategy optimization at low temperatures for li-ion batteries based on multi-factor coupling aging model | |
| CN114252795B (en) | Method for predicting cycle life of lithium ion battery | |
| CN112946501A (en) | Method for rapidly testing cycle life of lithium ion battery | |
| CN111366863A (en) | Lithium ion battery service life acceleration pre-judging method based on low-temperature circulation | |
| CN112946506B (en) | Method for rapidly testing cycle life of lithium ion battery | |
| CN106410304A (en) | Insufficient charging cycle system suitable for matching with lead-carbon battery in energy accumulation scene | |
| CN112946500B (en) | Method for rapidly testing cycle life of lithium ion battery | |
| KR20220052703A (en) | Method, battery management system, charging apparatus for charging secondary battery using silicon based negative electrode | |
| CN112946505B (en) | Method for rapidly testing cycle life of lithium ion battery | |
| CN112946502B (en) | Method for rapidly testing cycle life of lithium ion battery | |
| CN112946504B (en) | Method for rapidly testing cycle life of lithium ion battery | |
| CN112946503B (en) | Method for rapidly testing cycle life of lithium ion battery | |
| Lencwe et al. | Performance studies of lead acid batteries for transport vehicles | |
| WO2022198529A1 (en) | Method for charging battery, and electrical device and storage medium | |
| KR102455631B1 (en) | Method and apparatus of charging battery | |
| CN112666482A (en) | Method and system for testing cycle life of lithium ion battery | |
| CN113176519A (en) | Lithium ion battery service life acceleration method based on particle irradiation | |
| CN111755764A (en) | Method for reducing polarization of lithium battery |
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 | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |