Battery filling method and battery

Abstract

The present invention provides a battery injection method and a battery, the battery injection method comprising the following steps: injecting electrolyte into the battery for the first time before pre-charging the battery, the volume ratio of the injected electrolyte being 80% to 90%; injecting electrolyte into the battery for the second time after pre-charging the battery, the volume ratio of the injected electrolyte being 4.3% to 6.4%; injecting electrolyte into the battery for the third time after the battery is divided, and replenishing the volume ratio of the electrolyte to 100%. The present invention is conducive to meeting the battery pre-charging requirements by injecting electrolyte for the first time before pre-charging the battery, and is conducive to reducing the gas in the electrolyte by injecting electrolyte for the second time after pre-charging and injecting electrolyte for the third time after the battery is divided, thereby facilitating improving the bonding effect between the pole pieces in the battery, thereby facilitating good bonding between the pole pieces during the charging and discharging process of the battery, and having no abnormal interface, thereby facilitating improving the safety performance and cycle performance of the battery, and also facilitating reducing the production cost.

Description

Technical Field

[0001] The present invention relates to the technical field of power batteries, and in particular to a battery injection method. The present invention also relates to a battery injected with the injection method. Background Art

[0002] Blade batteries have the advantages of high volume utilization, low heat generation and heat dissipation, and are increasingly being used. Currently, blade batteries can be made of lithium iron phosphate system, ternary system, cobalt-free system, etc. However, due to the long length, low width and thickness of blade batteries, the processing difficulty is greatly increased. At present, blade batteries are prone to abnormalities such as black spots and electrode wrinkles on the interface after capacity division, which affects the cycle performance of blade batteries.

[0003] The scheme of restraining the battery only during the process of charging and discharging in the prior art can no longer achieve the ideal effect. Because there are normal pressure gas, electrolyte and pole group inside the battery, the internal space of the battery will be compressed during the restraint of the battery cell, which will increase the internal pressure of the battery and make it impossible to continue restraining, otherwise the sealing nail will burst out. And as the battery is charged, the expanded pole group will become soft and loose, resulting in poor fit between the pole pieces and easy to appear black spots. In addition, the battery needs to be restrained and operated throughout the whole process, which makes the cost of the whole process high. The compression of the internal space of the battery also makes it difficult to inject liquid, thereby limiting the amount of liquid injected into the battery. Summary of the invention

[0004] In view of this, the present invention aims to provide a battery injection method to improve the safety performance and cycle performance of the battery and help reduce production costs.

[0005] To achieve the above object, the technical solution of the present invention is achieved as follows:

[0006] A battery injection method comprises the following steps:

[0007] Before the battery is pre-charged, an electrolyte is first injected into the battery, and the volume ratio of the injected electrolyte is 80% to 90%;

[0008] After the battery is pre-charged, the electrolyte is injected into the battery for the second time, and the volume ratio of the injected electrolyte is 4.3% to 6.4%;

[0009] After the battery capacity is divided, the electrolyte is injected into the battery for the third time to replenish the volume ratio of the electrolyte to 100%.

[0010] Furthermore, the volume ratio of the electrolyte injected for the first time is 85%.

[0011] Furthermore, the volume ratio of the electrolyte injected for the second time is 5%.

[0012] Furthermore, after injecting the electrolyte for the second time and before dividing the capacity of the battery, the battery is squeezed to exhaust air.

[0013] Furthermore, in the extrusion exhaust step, the sealing component on the sealed injection hole is first removed, and the two sides of the battery are squeezed to discharge the gas in the electrolyte, and finally the injection hole is sealed by a sealing member.

[0014] Furthermore, in the extrusion exhaust step, both sides of the battery are squeezed from the bottom of the battery to the top to exhaust the gas in the electrolyte.

[0015] Furthermore, in the extrusion exhaust step, the battery is extruded using two oppositely disposed pressing rollers;

[0016] The pressing roller can rotate around its own axis and move from the bottom to the top of the battery.

[0017] Furthermore, the pressing roller has a radially outwardly protruding rolling protrusion, and the pressing roller presses the battery through the rolling protrusion;

[0018] The length of the rolling protrusion is less than or equal to the width of the battery.

[0019] Furthermore, after the battery capacity division step, the plugging piece of the liquid injection hole is removed, and the sealing hole is welded to seal the liquid injection hole.

[0020] Compared with the prior art, the present invention has the following advantages:

[0021] The battery injection method described in the present invention helps to meet the battery pre-charging requirements by injecting electrolyte for the first time before the battery is pre-charged, and helps to reduce the gas in the electrolyte by injecting electrolyte for the second time after the pre-charging, and injecting electrolyte for the third time after the battery is divided, thereby helping to improve the bonding effect between the pole pieces in the battery, thereby helping to ensure good bonding between the pole pieces during the charging and discharging process of the battery, and no abnormalities in the interface, thereby helping to improve the safety performance and cycle performance of the battery, and also helping to reduce production costs.

[0022] In addition, another object of the present invention is to provide a battery, wherein the electrolyte in the battery is injected using the battery injection method as described above.

[0023] The battery of the present invention, by adopting the above-mentioned liquid injection method, is beneficial to improving the safety of the battery and has a better use effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:

[0025] Figure 1 is a flow chart of the liquid injection method according to an embodiment of the present invention;

[0026] Figure 2 A schematic diagram of the positional relationship between the pressing roller and the battery according to an embodiment of the present invention;

[0027] Figure 3 It is a schematic diagram of the structure of the exhaust device according to an embodiment of the present invention;

[0028] Description of reference numerals:

[0029] 1. Battery; 2. Pressing roller; 201. Rolling protrusion; 3. Bracket; 301. Pulley; 302. Conveyor belt; 303. Motor mounting seat; 304. Guide hole. DETAILED DESCRIPTION

[0030] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0031] In the description of the present invention, it should be noted that if there are terms indicating orientation or positional relationship such as "upper", "lower", "inner", "back", etc., they are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, if there are terms such as "first", "second", etc., they are also used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0032] The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments.

[0033] The present embodiment relates to a battery injection method, comprising the following steps: before the battery 1 is pre-charged and formed, an electrolyte is injected into the battery 1 for the first time, and the volume ratio of the injected electrolyte is 80% to 90%; after the battery 1 is pre-charged, an electrolyte is injected into the battery 1 for the second time, and the volume ratio of the injected electrolyte is 4.3% to 6.4%; after the battery 1 is divided, an electrolyte is injected into the battery 1 for the third time to replenish the volume ratio of the electrolyte to 100%.

[0034] Based on the above overall introduction, in the injection method described in this embodiment, Figure 1As shown in , the amount of electrolyte injected into the battery 1 before the pre-charging of the battery 1 should meet the electrolyte demand of the battery 1 in the pre-charging stage, and the SEI film in the battery 1 is well formed. In specific implementation, the volume ratio of the electrolyte injected for the first time is 85%. Of course, the volume ratio of the electrolyte injected for the first time can also be 80%, 82%, 84%, 86%, 88% or 90%, etc.

[0035] When the electrolyte is injected into the battery 1 for the second time after the battery 1 is pre-charged, the electrolyte should not flow out of the battery 1 when the battery 1 is restrained. On the premise of meeting the sufficient electrolyte demand of the battery 1 during the capacity division stage, after multiple tests and verifications, it is determined that the volume ratio of the second electrolyte injection is 4.3% to 6.4%. In specific implementation, the volume ratio of the second electrolyte injection is 5%. Of course, the volume ratio of the electrolyte here can also be 4.3%, 4.5%, 5%, 5.5%, 6% or 6.4%, etc.

[0036] To further improve the safety of the battery 1, in this embodiment, after the second injection of electrolyte and before the battery 1 is divided, the battery 1 is squeezed to exhaust. In the squeezing and exhausting step, the sealing component on the sealing injection hole, such as a sealing nail, is first removed, and the two sides of the battery 1 are squeezed to discharge the gas in the electrolyte, and finally the injection hole is temporarily blocked by the blocking member.

[0037] As a preferred embodiment, in the extrusion exhaust step, the two sides of the battery 1 are squeezed from the bottom to the top of the battery 1 to exhaust the gas in the electrolyte. This is conducive to improving the exhaust efficiency and exhaust volume of the gas in the electrolyte. Specifically, in this embodiment, two oppositely arranged pressing rollers 2 are used to squeeze the battery 1. The pressing rollers 2 can rotate around their own axes and move from the bottom to the top of the battery 1. Figure 2 and Figure 3 As shown in , the pressing rollers 2 are respectively arranged on both sides of the thickness direction of the battery 1. In order to further improve the exhaust effect of the pressing roller 2, in this embodiment, the pressing roller 2 has a radially outwardly protruding rolling protrusion 201, and the pressing roller 2 rolls the battery 1 through the rolling protrusion 201, and the length of the rolling protrusion 201 is less than the width of the battery 1.

[0038] In this embodiment, when the battery 1 is squeezed by the pressing roller 2, the rolling protrusion 201 can squeeze the middle part of the battery 1 along the length direction of the battery 1, so as to improve the gas discharge efficiency. At the same time, by making the length of the rolling protrusion 201 smaller than the width of the battery 1, it is helpful to prevent the rolling protrusion 201 from squeezing the edges around the battery 1 shell, that is, the intersection of two adjacent side surfaces, so as to improve the stability of the battery 1 structure. Of course, the solution that the length of the rolling protrusion 201 is equal to the width of the battery 1 is also feasible.

[0039] In this embodiment, in order to improve the exhaust effect of the pressure roller 2 on the battery 1, a battery 1 exhaust device is also provided, such as Figure 3 As shown, the exhaust device includes two brackets 3 disposed on both sides of the battery 1, and a plurality of connecting plates connected between the two brackets 3. Each bracket 3 is provided with a guide hole 304 extending in the height direction. Each pressing roller 2 is disposed on the bracket 3 and moves up and down along the guide hole 304. In order to drive each pressing roller 2 to move from bottom to top, a belt pulley 301 disposed at intervals up and down is provided on the bracket 3, and a conveyor belt 302 is wound around the two belt pulleys 301.

[0040] In addition, a driving motor is provided on the bracket 3, and the power output end of the driving motor is connected to a pulley 301 thereof to drive the two pulleys 301 to drive the conveyor belt 302 to rotate. A motor mounting seat 303 is provided on the conveyor belt 302, and a motor is provided on the motor mounting seat 303, and the power output end of the motor is connected to one end of the pressure roller 2 to drive the pressure roller 2 to rotate around its own axis. Here, through the rotation of the conveyor belt 302, the pressure roller 2 can be driven to move from bottom to top through the motor mounting seat 303, and the pressure roller 2 can be driven to rotate by the motor, so that the battery 1 can be rolled to discharge the gas in the electrolyte.

[0041] When the battery 1 in this embodiment is exhausted by using the exhaust device, the battery 1 is fixed on the bracket 3. The fixing method of the battery 1 here can adopt the fixing structure of the battery 1 in the prior art, which will not be described in detail here.

[0042] In addition, in this embodiment, after the battery 1 capacity separation step, the sealing piece of the injection hole is removed, and the injection hole is welded, for example, the injection hole is sealed by welding a sealing nail, so that the sealing nail seals the injection hole, thereby completing the injection of electrolyte into the battery 1.

[0043] In the present embodiment, during the capacity division of the battery 1 , the battery 1 is placed on the battery 1 restraining mechanism, and the battery 1 is divided in capacity under the restraint state, which is conducive to meeting the demand for the capacity division of the battery 1 .

[0044] The battery injection method described in this embodiment helps to meet the pre-charging requirements of the battery 1 by injecting electrolyte for the first time before the battery 1 is pre-charged, and helps to reduce the gas in the electrolyte by injecting electrolyte for the second time after the pre-charging, and injecting electrolyte for the third time after the battery 1 is divided, thereby helping to improve the bonding effect between the pole pieces in the battery 1, so that the pole pieces of the battery 1 are well bonded during the charging and discharging process, and there is no abnormality in the interface, thereby helping to improve the safety performance and cycle performance of the battery 1, and also helping to reduce production costs.

[0045] In addition, this embodiment also relates to a battery 1, in which the electrolyte is injected by the battery injection method described above. The battery 1 described in this embodiment, by adopting the above injection method, is conducive to improving the safety of the battery 1 and has a better use effect.

[0046] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A battery injection method, characterized in that: The following steps are involved: Before the battery (1) is pre-charged, an electrolyte is first injected into the battery (1), and the volume ratio of the injected electrolyte is 80% to 90%; After the battery (1) is pre-charged, the electrolyte is injected into the battery (1) for a second time, with the volume ratio of the injected electrolyte being 4.3% to 6.4%; After the battery (1) is divided into two parts, the electrolyte is injected into the battery (1) for a third time to replenish the volume ratio of the electrolyte to 100%; After the second injection of the electrolyte and before the battery (1) is divided into two parts, the battery (1) is extruded and exhausted. In the extrusion and exhaust step, the sealing component on the sealing injection hole is first removed, and the two sides of the battery (1) are squeezed to discharge the gas in the electrolyte. Finally, the injection hole is sealed by a sealing member. In the extrusion and exhaust step, the two sides of the battery (1) are squeezed from the bottom of the battery (1) to the top to discharge the gas in the electrolyte. In the extrusion and exhaust step, the battery (1) is squeezed using two pressing rollers (2) arranged opposite to each other; The pressing roller (2) is capable of rotating around its own axis and moving from the bottom to the top of the battery (1); the pressing roller (2) is provided with a radially outwardly protruding rolling protrusion (201); the pressing roller (2) rolls the battery (1) via the rolling protrusion (201); the length of the rolling protrusion (201) is less than or equal to the width of the battery (1).

2. The battery injection method according to claim 1, characterized in that: The volume ratio of the electrolyte injected for the first time is 85%.

3. The battery injection method according to claim 1, characterized in that: The volume ratio of the electrolyte injected for the second time is 5%.

4. The battery injection method according to claim 1, characterized in that: After the battery (1) capacity division step, the plugging piece of the liquid injection hole is removed, and the liquid injection hole is welded to seal the liquid injection hole.

5. A battery, characterized in that: The electrolyte in the battery (1) is injected using the battery injection method described in any one of claims 1 to 4.

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