All-solid-state battery and formation process and preparation method thereof

Abstract

The invention discloses an all-solid-state battery as well as a formation process and a product thereof. The formation process comprises the following steps: step 1, applying pressure to the all-solid-state battery at 10KPa-200KPa through a clamp; 2, when the environment temperature T1 is the room temperature, the current of constant-current charging ranges from 0.05 C to 0.2 C till the first state of charge ranges from 5% to 15% SOC; 3, the environment temperature T2 is 45-80 DEG C, the current of constant-current charging is 0.2-0.5 C, and the second state of charge is 15%-65% SOC, or pulse charging is carried out; 4, the temperature of the environment where the all-solid-state battery is located is adjusted to be T3, constant-current charging is conducted to 100% SOC, and T3 is larger than T2 and larger than T1; and 5, performing constant-current discharge on the all-solid-state battery in the step 4 until the DOD of 30%-65% is cut off. According to the invention, the thickness consistency, the capacity consistency and the cycle performance of the battery are all improved by pressurizing the battery core and cooperating with stepped temperature and stage formation.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of batteries, and relates to a full solid-state battery and a formation process and preparation method thereof, in particular to a rapid and efficient solid-state battery formation process and a full solid-state battery prepared by the process. BACKGROUND

[0002] The development of battery technology has redefined energy, from electronic products to electric vehicles, battery technology has been everywhere. Lithium batteries have the advantages of high voltage, large specific energy, long charge and discharge life, safety and environmental protection, and are widely used in various electronic products (such as mobile phones, digital cameras, notebook computers, electric tools), portable small appliances, electric vehicles and energy storage systems. With the further improvement of the energy density and safety requirements of lithium ion batteries, solid-state batteries have become the future development direction.

[0003] The preparation process of lithium batteries is complex, including stirring, coating, drying, bare cell preparation, packaging and formation, etc., among which, the formation process is an indispensable process in the preparation process of lithium batteries, and plays a crucial role in the performance of lithium batteries. Formation refers to the first charge and discharge activation process of lithium ions, which can directly affect the rate performance, cycle and rate performance.

[0004] The traditional constant temperature and constant current formation method includes pre-charging: charging to 3.7V at a current of 0.20C, and then converting to constant voltage charging until the current decreases to 0.05C. The purpose of this step is to preliminarily activate the chemical substances inside the battery, and to prepare for the subsequent formation; formation: the formation process is usually divided into several stages. First, charge to 4.2V at a current of 0.20C, and then convert to constant voltage charging until the current decreases to 0.05C, and then discharge to 3.0V at a current of 0.20C. Next, charge to 4.2V at a current of 0.50C, and then convert to constant voltage charging until the current decreases to 0.05C, and then discharge to 3.0V at a current of 0.50C. This step will be repeated three times to ensure that the chemical reaction inside the battery reaches a stable state.

[0005] The interface of the lithium ion battery after the traditional constant temperature and constant current formation treatment is not good, and many black spots and lithium precipitation are prone to occur, and the capacity consistency, thickness consistency and electrical performance are difficult to improve. Moreover, this formation process is complex, many factors need to be controlled, the whole formation process needs a lot of time and operators, and a lot of cost and process time is wasted. The existing solid-state battery formation process is insufficient, and there is no suitable formation process for solid-state batteries. In view of the problems of the existing solid-state battery formation process.

[0006] The prior art is insufficient in discussing the solid-state battery production process, and the problem to be solved urgently in the promotion of the solid-state battery is that. Therefore, it is necessary to provide a formation method which is rapid, simple and can improve the performance of the all-solid-state battery. SUMMARY

[0007] The present application aims to provide a formation method of an all-solid-state battery, which realizes rapid and effective formation by pressing the battery cell through a clamp, controlling the temperature and mild polarization.

[0008] Still another object of the present application is to provide an all-solid-state battery product prepared by the above formation method.

[0009] The object of the present application is achieved by the following scheme: a formation method of an all-solid-state battery, comprising the following steps: Step one, applying a pressure of 10 KPa to 200 KPa to the all-solid-state battery through a clamp; Step two, constant current charging the original all-solid-state battery to a first state of charge, the current for constant current charging is 0.05C to 0.2C, the first state of charge is 5% to 15% SOC, and the temperature of the environment where the all-solid-state battery is located is T1, which is room temperature; Step three, changing the current, constant current charging the original all-solid-state battery to a second state of charge, wherein the current for constant current charging is 0.2C to 0.5C, the second state of charge is 15% to 65% SOC, and the temperature of the environment where the all-solid-state battery is located is T2, which is 45-80℃, or pulse charging the all-solid-state battery to a third state of charge; Step four, adjusting the temperature of the environment where the all-solid-state battery is located to T3, and constant current charging the all-solid-state battery to 100% SOC, wherein T2>T3>T1; Step five, constant current discharging the all-solid-state battery after step four to 30% to 65% DOD cutoff.

[0010] Preferably, the pressure applied by the clamp to the all-solid-state battery in step one is 10 KPa to 200 KPa; too small pressure cannot reduce the distance between the battery cells, and too large pressure can easily damage the battery.

[0011] Preferably, the current for constant current charging in step two is 0.05C to 0.2C, the first state of charge is 5% to 15% SOC, and the environment temperature is 25℃. The first step of constant current charging preliminarily activates the battery cell with appropriate current, at this time the negative electrode is in an empty state, and in 5%-15% SOC, direct current charging is not easy to produce larger polarization.

[0012] Preferably, the current of the constant current charging in step three is 0.2C to 0.5C, the first state of charge is 15% to 65% SOC, and the ambient temperature is 45-80℃. The process conditions of the pulse charging are as follows: positive pulse: current 0.2C to 0.5C; charging time 120s to 360s; resting for 10s; repeating 10 times; negative pulse: current 0.2C to 0.5C; charging time 100s to 300s; resting for 10s. A smaller polarization is generated, and the charging is performed in the mode of a single positive pulse; when the polarization increases, the single positive pulse cannot completely eliminate the polarization, and at this time, the combination of the positive pulse and the negative pulse is selected for charging. This process improves the charging speed and can eliminate the polarization caused by the improvement of the charging speed.

[0013] Preferably, the current of the constant current charging in step four is 0.5C to 1.5C, and the charging is performed to 100% SOC, and the ambient temperature is 25-45℃.

[0014] Preferably, the current of the constant current discharging in step five is 0.2C to 1.0C; and the constant current discharging is performed to 30% to 65% DOD.

[0015] The purpose of the present application is to provide a full solid-state battery prepared by the above formation process, and the rate and cycle performance of the battery are improved.

[0016] In the present application, the positive electrode main material of the solid-state battery is composed of one or more of LiCoO2, LiMnO2, LiFePO4, LiNi1-x-y Co x Mn y O2, Li1+xNi1-yMn y O2, Li1+xNiO2, LiM x O y X z (wherein M is a transition metal, X is a halogen element, x, y, and z are natural numbers), Li1+xCo1-yNiyO2(wherein 0.3≥x≥-0.3 and 0.8≥y≥0.3), and the like can provide one or more of the lithium ion materials.

[0017] In the present application, the negative electrode main material of the solid-state battery is composed of one or more of natural graphite, artificial graphite, and silicon-carbon material.

[0018] By adopting the above technical solution, the present application has the following beneficial effects: The application proposes that the full solid-state battery is formed under the pressure of the clamp, which can effectively improve the speed of solid-solid interface fitting and the degree of component mutual diffusion, thereby reducing the resistance caused by the gap between the two layers; in addition, the present formation process is beneficial to the formation of a relatively continuous and dense CEI film on the surface of the positive electrode, thereby improving the high-temperature cycle stability of the battery. It is beneficial to improve the mechanical strength of the generated CEI film and the high-temperature cycle stability of the battery. At the same time, the system side reaction is accelerated, the system after formation is more stable, and the cycle performance is better. The thickness consistency, capacity consistency and cycle performance of the obtained full solid-state battery are improved. DETAILED DESCRIPTION

[0019] In order to further explain the technical scheme of the application, the application will be described in detail below through specific examples.

[0020] The following implementation and comparative example use the following method for preparing the battery: The positive electrode is selected according to the mass fraction: NCM813 (a kind of positive electrode material of nickel-cobalt-manganese ternary lithium battery, wherein the nickel content is 80%, the cobalt content is 10%, and the manganese content is 10%) 96.5%, carbon nanotube (CNT) 1.0%, polyvinylidene fluoride (PVDF) 2%, and conductive carbon black (SP) 1.5%; The negative electrode is selected: silicon-carbon negative electrode 95.5%, carbon nanotube (CNT) 0.5%, sodium carboxymethyl cellulose (CMC) 1.2%, styrene-butadiene rubber (SBR) 1.3%, and polyacrylic acid (PAA) 1.5%; The Al foil is selected to be 10 um, and the Cu foil is selected to be 8 um; The positive electrode material is mixed uniformly according to the formula, coated on the Al foil, dried, cold-pressed, and the positive electrode sheet is obtained after sheeting; the negative electrode material is mixed uniformly according to the formula, coated on the Cu foil, dried, cold-pressed, and the negative electrode sheet is obtained after sheeting.

[0021] Then the positive electrode sheet and the negative electrode sheet are alternately stacked to obtain the unformed raw battery. Then, after injecting the conductive solution, the polymer monomer and the initiator, the battery is packaged.

[0022] Example 1 A formation method of a full solid-state battery, according to the following steps: Step one, after injecting the conductive solution, the polymer monomer and the initiator, the battery is packaged, and the 9 solid-state batteries are placed on the clamp after standing, and the pressure is increased to 60KPa, and the battery is placed on the formation cabinet; Step two, at 25℃, the battery is charged with constant current, and the battery is first charged with a current of 0.1C to 5% SOC, and is placed for 10min; Step three, adjust the ambient temperature of the battery to 65℃, and stand for 120 min. Charge to 45% SOC at a current of 0.2C, and stop heating after standing for 30 min; Step four, adjust the ambient temperature of the battery to 35℃, and charge to 100% SOC at a current of 0.5C, and stand for 10 min; Step five, adjust the ambient temperature of the battery to 25℃, and discharge at a constant current of 0.5C, and the depth of discharge is 35% DOD.

[0023] The batch of batteries is marked as batch A during circulation.

[0024] The battery formed by the method in this embodiment has a capacity retention rate of 87.2% after 800 cycles of 0.5C charging and 1C discharging at room temperature, as shown in Table 1. The battery formed by the method in this embodiment has a capacity retention rate of 94.8% after 200 cycles of 1.5C charging and 1C discharging at 25℃, as shown in Table 2. The battery formed by the method in this embodiment has a capacity retention rate of 95.2% after 200 cycles of 1.5C charging and 1C discharging at 45℃, as shown in Table 3.

[0025] Example 2 A formation method of a full solid-state battery, according to the following steps: Step one, after the semi-finished product battery is injected with conductive solution, polymer monomer and initiator, and is packaged and placed, 9 solid-state batteries are clamped on the fixture, and the pressure is increased to 60KPa and placed on the formation cabinet; Step two, at 25℃, the above-mentioned battery is charged at a constant current, and the battery is first charged to 5% SOC at a current of 0.1C, and stands for 10 min; Step three, adjust the ambient temperature of the battery to 65℃, and stand for 120 min. Charge to 45% SOC at a current of 0.2C, and stop heating after standing for 30 min; Step four, adjust the ambient temperature of the battery to 35℃, and charge to 100% SOC at a current of 0.5C, and stand for 10 min; Step five, adjust the ambient temperature of the battery to 25℃, and discharge at a constant current of 0.5C, and the depth of discharge is 35% DOD. The batch of batteries is marked as batch B during circulation.

[0026] The battery formed by the method in this embodiment has a capacity retention rate of 88.5% after 800 cycles of 0.5C charging and 1C discharging at room temperature, as shown in Table 1. The battery formed by the method in this embodiment has a capacity retention rate of 97.2% after 200 cycles of 1.5C charging and 1C discharging at 25℃, as shown in Table 2. The battery of the formation method of the present embodiment has a capacity retention rate of 97.7% after 1.5C charging and 1C discharging for 200 cycles at 45°C, as shown in Table 3.

[0027] Example 3 A formation method of a full solid-state battery, according to the following steps: Step one, after injecting the semi-finished product battery with conductive solution, polymer monomer and initiator, and packaging, placing 9 solid-state batteries on the clamp and pressurizing to 60KPa, and placing them on the formation cabinet; Step two, at 25°C, the above-mentioned battery is charged with constant current, first charging the battery to 5% SOC with a current of 0.1C, and standing for 10min; Step three, adjusting the ambient temperature of the battery to 65°C, standing for 120min, charging to 45% SOC with a current of 0.2C, and stopping heating after standing for 30min; Step four, adjusting the ambient temperature of the battery to 35°C, charging to 100% SOC with a current of 0.5C, and standing for 10min; Step five, adjusting the ambient temperature of the battery to 25°C, discharging with constant current, 0.5C current, and 35% DOD.

[0028] The batch of batteries is marked as batch C during circulation.

[0029] The battery of the formation method of the present embodiment has a capacity retention rate of 87.7% after 0.5C charging and 1C discharging for 800 cycles at room temperature, as shown in Table 1. The battery of the formation method of the present embodiment has a capacity retention rate of 96.3% after 1.5C charging and 1C discharging for 200 cycles at 25°C, as shown in Table 2. The battery of the formation method of the present embodiment has a capacity retention rate of 96.8% after 1.5C charging and 1C discharging for 200 cycles at 45°C, as shown in Table 3.

[0030] Example 4 A formation method of a full solid-state battery, according to the following steps: Step one, after injecting the semi-finished product battery with conductive solution, polymer monomer and initiator, and packaging, placing 9 solid-state batteries on the clamp and pressurizing to 60KPa, and placing them on the formation cabinet; Step two, at 25°C, the above-mentioned battery is charged with constant current, first charging the battery to 5% SOC with a current of 0.1C, and standing for 10min; Step three, adjusting the ambient temperature of the battery to 65°C, standing for 120min, charging to 45% SOC with a current of 0.2C, and stopping heating after standing for 30min; Step four, adjust the ambient temperature of the battery to 35℃, charge to 100% SOC at 0.5C current, and stand for 10 min; Step five, constant current discharge the full solid-state battery in step three to a certain depth cut-off; wherein T3>T2>T1.

[0031] Step five, adjust the ambient temperature of the battery to 25℃, constant current discharge, current 0.5C, discharge depth 35% DOD.

[0032] The batch of batteries is marked as batch D when circulating.

[0033] The battery of the formation method of the present embodiment has a capacity retention rate of 86.9% after 800 cycles of 0.5C charging and 1C discharging at room temperature, as shown in Table 1; The battery of the formation method of the present embodiment has a capacity retention rate of 96.0% after 200 cycles of 1.5C charging and 1C discharging at 25℃, as shown in Table 2; The battery of the formation method of the present embodiment has a capacity retention rate of 96.2% after 200 cycles of 1.5C charging and 1C discharging at 45℃, as shown in Table 3.

[0034] Example 5 A formation method of a full solid-state battery, according to the following steps: Step one, take the semi-finished product battery cell, inject conductive solution, polymer monomer and initiator, and then package, after standing, clamp 9 solid-state batteries on the fixture, pressurize to 60KPa, and place on the formation cabinet; Step two, constant current charge the above-mentioned battery at 25℃, first charge the battery to 5% SOC at 0.1C current, and stand for 10 min; Step three, adjust the ambient temperature of the battery to 65℃, stand for 120 min, charge to 45% SOC at 0.2C current, and stop heating after standing for 30 min; Step four, adjust the ambient temperature of the battery to 35℃, charge to 100% SOC at 0.5C current, and stand for 10 min; Step five, adjust the ambient temperature of the battery to 25℃, constant current discharge, current 0.5C, discharge depth 35% DOD.

[0035] The batch of batteries is marked as batch E when circulating.

[0036] The battery of the formation method of the present embodiment has a capacity retention rate of 85.9% after 800 cycles of 0.5C charging and 1C discharging at room temperature, as shown in Table 1; The battery of the formation method of the present embodiment has a capacity retention rate of 94.2% after 200 cycles of 1.5C charging and 1C discharging at 25℃, as shown in Table 2; The battery of the formation method of the present embodiment has a capacity retention rate of 94.5% after 1.5C charging and 1C discharging for 200 cycles at 45°C, as shown in Table 3.

[0037] Example 6 A formation method of a full solid-state battery, according to the following steps: Step one, take the semi-finished product battery, inject the conductive solution, polymer monomer and initiator, and then package, after the completion of the standing, clamp the 9 solid-state batteries, press to 60KPa, and place on the formation cabinet; Step two, at 25°C, the above-mentioned battery is charged with constant current, first charge the battery to 5% SOC with 0.1C current, and stand for 10min; Step three, adjust the ambient temperature of the battery to 65°C, stand for 120min, charge to 45% SOC with 0.2C current, and stop heating after standing for 30min; Step four, adjust the ambient temperature of the battery to 35°C, charge to 100% SOC with 0.5C current, and stand for 10min; Step five, adjust the ambient temperature of the battery to 25°C, discharge with constant current, the current is 0.5C, and the depth of discharge is 35% DOD.

[0038] Step five, mark the batch of batteries as F batch during circulation.

[0039] The battery of the formation method of the present embodiment has a capacity retention rate of 86.2% after 0.5C charging and 1C discharging for 800 cycles at room temperature, as shown in Table 1; The battery of the formation method of the present embodiment has a capacity retention rate of 96.3% after 1.5C charging and 1C discharging for 200 cycles at 25°C, as shown in Table 2; The battery of the formation method of the present embodiment has a capacity retention rate of 96.6% after 1.5C charging and 1C discharging for 200 cycles at 45°C, as shown in Table 3.

[0040] Comparative Example 1 After the completion of the standing, place the 9 solid-state batteries on the formation cabinet without clamps, charge with constant current at 0.2C at 25°C, and charge to 60% SOC of the battery. Mark the batch of batteries as X batch during circulation.

[0041] Comparative Example 2 After the completion of the standing, place the 9 solid-state batteries on the formation cabinet with clamps, press to 50KPa, charge with constant current at 0.1C at 25°C, and charge to 60% SOC of the battery. Mark the batch of batteries as Y batch during circulation.

[0042] Comparative Example 3 After the 9 solid-state batteries after standing are placed on the formation cabinet, the upper clamp is pressed to 50 KPa, and constant current charging is carried out at 25°C with a current of 0.2C to charge the battery to 80% SOC. The batch of batteries is marked as Z batch during circulation.

[0043] The rate and cycle performance of the all-solid-state battery formed by the application are effectively improved.

[0044] Table 1 lists the cycle number and capacity retention rate of the battery of the example and the comparative example after 800 cycles; Table 2 lists the cycle number and capacity retention rate of the battery of the example and the comparative example after 200 cycles at 25°C; Table 3 lists the cycle number and capacity retention rate of the battery of the example and the comparative example after 200 cycles at 45°C high temperature.

[0045] After the A-D and X-Z batches of batteries obtained by the formation process and the conventional formation method are aged, rested, and separated, one battery with similar capacity and internal resistance is selected from each batch, and is sequentially marked as A1, B1, C1, D1, and X1-Z1. The cycle test is carried out at 25°C with 0.5C charging and 1C discharging, and the cycle number when the remaining capacity of each battery is reduced to 95% of the initial capacity is recorded as shown in Table 1.

[0046] After the A-D and X-Z batches of batteries obtained by the formation process and the conventional formation method are aged, rested, and separated, one battery with similar capacity and internal resistance is selected from each batch. The cycle test is carried out at 45°C with 1.0C charging and 1C discharging, and the cycle number when the remaining capacity of each battery is reduced to 90% of the initial capacity is recorded as shown in Table 1: .

[0047] After the A-D and X-Z batches of batteries obtained by the formation process and the conventional formation method are aged, rested, and separated, one battery with similar capacity and internal resistance is selected from each batch. The cycle test is carried out at 25°C with 1.5C charging and 1C discharging, and the capacity retention rate of each battery is recorded as shown in Table 2.

[0048] After the A-D and X-Z batches of batteries obtained by the formation process and the conventional formation method are aged, rested, and separated, one battery with similar capacity and internal resistance is selected from each batch. The cycle test is carried out at 25°C with 1.5C charging and 1C discharging, and the capacity retention rate of each battery is recorded as shown in Table 2. .

[0049] In combination with the process parameters and the data in Tables 1, 2 and 3, it can be seen that: the cell is charged to 5% SOC at 0.1C in S1 under a pressure of 150 KPa; the cell is charged to 45% SOC at 65°C in S2; the cell is charged to 100% SOC at 35°C in S3; finally, the cell is discharged at a constant current of 0.5C, and the cell prepared after a discharge depth of 35% DOD is significantly improved in cycle life and battery performance. It is proved that the pressing by the clamp, the formation SOC and the temperature can effectively improve the contact interface resistance of the solid-solid interface and effectively improve the cycle performance of the solid-state battery.

[0050] It can be seen from the comparison of the examples and Comparative Examples 1-3 that the all-solid-state cell is formed under the pressing of the clamp, which can effectively improve the speed of the solid-solid interface fitting and the degree of mutual diffusion of components, thereby reducing the resistance caused by the gap between the two layers; in addition, the present formation process is beneficial to the formation of a relatively continuous and dense CEI film on the surface of the positive electrode, thereby improving the high-temperature cycle stability of the battery. It is beneficial to improve the mechanical strength of the generated CEI film and the high-temperature cycle stability of the battery. At the same time, the system side reaction is accelerated, the system after formation is more stable, and the cycle performance is better.

Claims

1. A method for forming an all-solid-state battery, characterized in that: Includes the following steps: Step 1: Apply a pressure of 10 kPa to 200 kPa to the all-solid-state battery using a clamp; Step 2: At an ambient temperature of T1 (room temperature), charge the original all-solid-state battery with a constant current to the first state of charge (SOC). The constant current charging current is 0.05C to 0.2C, and the first SOC is 5% to 15%. Step 3: Change the current and charge to the second state of charge using constant current. The constant current charging current is 0.2C to 0.5C, the second state of charge is 15% to 65% SOC, the ambient temperature T2 of the all-solid-state battery is 45-80℃, or pulse charging. Step 4: Adjust the ambient temperature of the all-solid-state battery to T3, and charge the all-solid-state battery with constant current to 100% SOC, where T2 > T3 > T1; Step 5: After step 4, the all-solid-state battery is discharged at a constant current until it reaches 30% to 65% DOD (Dies of Discharge) cutoff.

2. The formation method of the all-solid-state battery as described in claim 1, characterized in that: In step two, the ambient temperature T1 is 25℃.

3. The formation method of the all-solid-state battery as described in claim 1, characterized in that: In step three, the pulse charging process conditions are as follows: Forward pulse: Current 0.2C to 0.5C; charging time 120s to 360s; rest for 10s; repeat 10 times; Reverse pulse: Current 0.2C to 0.5C; charging time 100s to 300s; rest for 10s.

4. The formation method of the all-solid-state battery as described in claim 1, characterized in that: In step four, the constant current charging current is 0.5C to 1.5C, charging to 100% SOC, with an ambient temperature of 25-45℃.

5. The formation method of the all-solid-state battery as described in claim 1, characterized in that: In step four, the constant current discharge current is 0.2C to 1.0C; the constant current discharge is 30% to 65% DOD.

6. The formation method of an all-solid-state battery according to any one of claims 1 to 5, characterized in that: Follow these steps: Step 1: After injecting conductive solution, polymer monomer and initiator into the semi-finished battery cell, encapsulate and set aside; then place the 9 solid-state batteries onto the clamp, pressurize to 60 kPa, and place them on the formation cabinet. Step 2: At 25°C, charge the battery at a constant current. First, charge the battery to 5% SOC with a current of 0.1C, and let it rest for 10 minutes. Step 3: Adjust the ambient temperature of the battery to 65℃, let it rest for 120 minutes, charge it to 45% SOC with a current of 0.2C, let it rest for 30 minutes and then stop heating. Step 4: Adjust the ambient temperature of the battery to 35℃, charge it to 100% SOC at a current of 0.5C, and let it rest for 10 minutes. Step 5: Adjust the ambient temperature of the battery to 25℃, perform constant current discharge at 0.5C, and achieve a depth of discharge of 35% DOD.

7. The formation method of an all-solid-state battery according to any one of claims 1 to 5, characterized in that: Follow these steps: Step 1: After injecting conductive solution, polymer monomer and initiator into the semi-finished battery cell, encapsulate it and let it rest; then place the 9 solid-state batteries on the clamp, pressurize to 60 kPa and place them on the formation cabinet. Step 2: At 25°C, charge the battery at a constant current. First, charge the battery to 5% SOC with a current of 0.1C, and let it rest for 10 minutes. Step 3: Adjust the ambient temperature of the battery to 65℃, let it rest for 120 minutes, charge it to 45% SOC with a current of 0.2C, let it rest for 30 minutes and then stop heating; Step 4: Adjust the ambient temperature of the battery to 35℃, charge it to 100% SOC at a current of 0.5C, and let it rest for 10 minutes. Step 5: Adjust the ambient temperature of the battery to 25℃, perform constant current discharge at 0.5C current, and achieve a depth of discharge of 35% DOD.

8. The formation method of an all-solid-state battery according to any one of claims 1 to 5, characterized in that: Follow these steps: Step 1: After injecting conductive solution, polymer monomer and initiator into the semi-finished battery cell, encapsulate it and let it rest; then place the 9 solid-state batteries on the clamp, pressurize to 60 kPa and place them on the formation cabinet. Step 2: At 25°C, charge the battery at a constant current. First, charge the battery to 5% SOC with a current of 0.1C, and let it rest for 10 minutes. Step 3: Adjust the ambient temperature of the battery to 65℃, let it rest for 120 minutes, charge it to 45% SOC with a current of 0.2C, let it rest for 30 minutes and then stop heating; Step 4: Adjust the ambient temperature of the battery to 35℃, charge it to 100% SOC at a current of 0.5C, and let it rest for 10 minutes. Step 5: Adjust the ambient temperature of the battery to 25℃, perform constant current discharge at 0.5C, and achieve a depth of discharge of 35% DOD.

9. The formation method of an all-solid-state battery according to any one of claims 1 to 5, characterized in that: Follow these steps: Step 1: Take the semi-finished battery cell, inject conductive solution, polymer monomer and initiator and then encapsulate it. After it is set aside, put the 9 solid batteries on the clamp, pressurize them to 60 kPa and place them on the formation cabinet. Step 2: At 25°C, charge the battery at a constant current. First, charge the battery to 5% SOC with a current of 0.1C, and let it rest for 10 minutes. Step 3: Adjust the ambient temperature of the battery to 65℃, let it rest for 120 minutes, charge it to 45% SOC with a current of 0.2C, let it rest for 30 minutes and then stop heating; Step 4: Adjust the ambient temperature of the battery to 35℃, charge it to 100% SOC at a current of 0.5C, and let it rest for 10 minutes. Step 5: Adjust the ambient temperature of the battery to 25℃, perform constant current discharge at 0.5C, and achieve a depth of discharge of 35% DOD.

10. An all-solid-state battery prepared by the formation method according to any one of claims 1 to 9.

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