CN-121769179-B - Automatic assembly method, system, medium and product of all-solid-state die test battery

CN121769179BCN 121769179 BCN121769179 BCN 121769179BCN-121769179-B

Abstract

The application provides an automatic assembly method, a system, a medium and a product of an all-solid-state battery test, and relates to the field of solid-state battery assembly, wherein the method comprises the steps of controlling a pressurizing unit to apply pressure to an all-solid-state battery die along the axial direction until a target pressure maintaining state is reached; the method comprises the steps of driving a screw locking unit to screw a fastener into an all-solid-state battery mold in the process of maintaining a target pressure maintaining state, monitoring an axial load response parameter of a pressurizing unit in real time, stopping the screw locking unit from screwing in when the axial load response parameter is monitored to reach a preset load transfer threshold value to obtain a pressure locked mold assembly, and controlling the pressurizing unit to remove external pressure from the mold assembly according to a preset curve to obtain an all-solid-state battery mold finished product. By implementing the method, seamless connection of the fastener to internal pressure before external pressure is removed can be realized, and the authenticity and accuracy of the internal forming pressure of the all-solid-state battery die are ensured.

Inventors

ZHOU YANG
LI LIN
YANG XIAOLU
Qi Qiongqiong

Assignees

元能科技（厦门）有限公司

Dates

Publication Date: 20260512
Application Date: 20260303

Claims (9)

1. An automated assembly method of an all-solid-state battery test, applied to an automated assembly system of an all-solid-state battery test, the system comprising a pressurizing unit, an all-solid-state battery mold, and a screw locking unit, the method comprising: Controlling a pressurizing unit to apply pressure to an all-solid-state battery die along the axial direction until a target pressure maintaining state is reached, wherein the target pressure maintaining state is a physical state that a solid electrolyte layer in the all-solid-state battery die is compressed to a preset density and the pressurizing unit actively maintains constant pressure; driving a screw locking unit to screw a fastener into the all-solid-state battery mold in the process of maintaining the target pressure maintaining state, and monitoring an axial load response parameter of the pressurizing unit in real time, wherein the axial load response parameter comprises an output force attenuation amount or a position compensation amount generated by the pressurizing unit for maintaining the target pressure maintaining state, and the step of driving the screw locking unit to screw the fastener into the all-solid-state battery mold in the process of maintaining the target pressure maintaining state comprises the following steps of: Controlling the screw locking unit to screw the fastening piece with a first axial tightening force until the axial load response parameter is monitored to reach a preset switching threshold value, wherein the switching threshold value is smaller than a preset load transfer threshold value; switching an axial control mode of the screw locking unit to a floating follower mode in which a second axial tightening force exerted by the screw locking unit is reduced to a minimum contact force that maintains an effective torque transmitting connection of its drive head with the fastener; Continuing to drive the fastener into rotation in the floating follower mode until the axial load response parameter is monitored to reach the load transfer threshold; Stopping the screwing action of the screw locking unit when the axial load response parameter is monitored to reach a preset load transfer threshold value, so as to obtain a pressure-locked die assembly, wherein the load transfer threshold value is a critical value interval in which the axial pretightening force generated by the fastener can balance the resilience force of the solid electrolyte layer; and controlling the pressurizing unit to remove external pressure from the die assembly according to a preset curve to obtain an all-solid-state battery die finished product.
2. The method according to claim 1, wherein the step of controlling the pressurizing unit to apply pressure to the all-solid-state battery mold in the axial direction until the target pressure maintaining state is reached, specifically comprises: Controlling the pressurizing unit to switch to a constant output force mode to continuously load the all-solid-state battery die, so as to obtain a constant voltage holding process; Acquiring an axial position change derivative of the pressurizing unit in real time in the constant pressure maintaining process to obtain an axial displacement rate; And when the axial displacement rate is detected to meet a preset creep convergence threshold, judging that the all-solid-state battery mold reaches the target pressure maintaining state.
3. The method of claim 1, further comprising, prior to the step of monitoring that the axial load response parameter reaches a preset load transfer threshold: Acquiring the material elastic modulus of the all-solid-state battery mold and the screw fit clearance parameter of the fastener; Calculating an axial displacement loss amount expected to occur at the moment of external pressure removal based on the elastic modulus of the material and the screw fit clearance parameter, and converting the axial displacement loss amount into a corresponding stress rebound compensation amount; And superposing the stress rebound compensation quantity to a theoretical value representing a rebound force balance point of the solid electrolyte layer, and calculating to obtain the load transfer threshold value containing the interference locking requirement.
4. The method of claim 1, further comprising, after the step of stopping the screwing action of the screw locking unit to obtain a pressure-locked mold assembly: Controlling the screw locking unit to execute a micro-retraction motion along the axial direction so as to remove the axial operation pressure applied to the all-solid-state battery mould by the screw locking unit; Collecting a pressure return value of the pressurizing unit after the micro-retraction action is executed, and judging whether the pressure return value exceeds a preset safety tolerance; if the pressure rise value exceeds the preset pressure rise value, judging that the fastener does not fully bear the rebound force of the solid electrolyte layer, calculating an additional screwing angle based on the pressure rise value, and re-driving the screw locking unit to execute compensation screwing.
5. The method according to claim 4, wherein said step of controlling said pressurizing unit to remove external pressure from said mold assembly according to a predetermined profile to obtain an all-solid-state battery mold finished product comprises: Controlling the pressurizing unit to execute a step-type unloading action, wherein the step-type unloading action comprises a plurality of pressure maintaining platforms which are gradually decreased; Monitoring the axial rebound displacement of the all-solid-state battery mould during each pressure maintaining platform, and calculating the unloading rigidity of the pressurizing unit at the current stage according to the axial rebound displacement; If the deviation value of the unloading stiffness and the prestored theoretical tensile stiffness of the fastener is in a preset linear matching interval, executing the unloading action of the next stage until the external pressure is completely removed; and if the unloading rigidity is detected to be suddenly changed or to exceed the linear matching interval, judging that the fastener is in slip failure, and controlling the pressurizing unit to immediately stop unloading and restore to the target pressure maintaining state.
6. The method of claim 5, further comprising, prior to the step of controlling the pressurizing unit to perform a stepped unloading action: Controlling the pressurizing unit to execute at least one stress breathing cycle on the die assembly, wherein the stress breathing cycle comprises that after the external pressure is reduced to a preset percentage of the target pressure maintaining state, the pressure is loaded back to an overpressure fluctuation value of the target pressure maintaining state again; monitoring whether the screw locking unit has a change in screwing angle or torque attenuation before and after the stress breathing cycle is executed; And if the change of the screwing angle or the torque attenuation is detected, driving the screw locking unit to execute secondary screwing under the state of maintaining the overvoltage fluctuation value.
7. The automatic assembly system for the all-solid-state die test battery is characterized by comprising a pressurizing unit, a screw locking unit and a control center which is in communication connection with the pressurizing unit and the screw locking unit, wherein the control center comprises one or more processors and a memory; The memory is coupled with the one or more processors, the memory for storing computer program code comprising computer instructions that the one or more processors call to cause the control center to cooperatively control the pressurizing unit and the screw locking unit to perform the method of any of claims 1-6.
8. A computer readable storage medium comprising instructions that, when run on an automated assembly system for all-solid-state mold test cells, cause the system to perform the method of any of claims 1-6.
9. A computer program product comprising computer programs/instructions which, when run on an automated assembly system for all-solid-state die test cells, cause the system to perform the method of any of claims 1-6.

Description

Automatic assembly method, system, medium and product of all-solid-state die test battery Technical Field The application relates to the field of solid-state battery assembly, in particular to an automatic assembly method, a system, a medium and a product of an all-solid-state die test battery. Background With the urgent demands for high energy density and high safety in the new energy field, all-solid-state batteries have become the core direction of the development of next-generation power batteries. In the material screening and process verification stage of all-solid-state batteries, to eliminate solid-solid interface impedance and ensure ion transport efficiency, it is often necessary to test the battery for performance testing using a dedicated all-solid-state mold. In the process of assembling the die battery, the internal solid electrolyte powder and the anode and cathode materials are required to be compacted and molded under extremely high axial pressure, and the high-pressure state is required to be locked for a long time through the fastening structure of the die, so that the high-pressure working environment in an actual battery stack is simulated, and the accuracy and the repeatability of electrochemical test data are ensured. In the related art, the mainstream technical means is to adopt a step-by-step "press-lock" combination scheme. Specifically, the mold filled with powder material is first set on the workbench of servo press or hydraulic press, the press is controlled to output one constant set pressure value, so that the powder inside the mold is compacted to set thickness or density, and then the locking bolt or nut around the mold is screwed with manual or matched electric tightening gun until the torque value fed back by the tightening gun reaches the preset technological standard, i.e. the fixed torque tightening mode. After all the fasteners reach the set torque, the press releases the external pressure and retracts, and the physical packaging of the die battery is completed. However, due to the extreme variability of friction coefficients during threading, the achievement of set torque is not directly equivalent to the fastener generating sufficient axial preload to fully balance the elastic resilience of the internal solid electrolyte layer. Under the existing operation, the substantial correlation judgment of the load transmission between the external press and the internal fastening piece is lacking, and when the external press removes the pressure, if the actual axial pulling force of the fastening piece is smaller than the rebound pushing force of the internal powder, the solid electrolyte layer in the die can generate instantaneous axial micro-expansion. Such invisible microscopic rebound may cause the actual pressure inside the packaged die battery to be substantially lower than the target pressure during pressurization, and the degree of pressure loss of the dies of different batches is irregular, which seriously interferes with the authenticity of electrochemical performance evaluation of the all-solid-state battery material. Disclosure of Invention The application provides an automatic assembly method, a system, a medium and a product of an all-solid-state die test battery, which are used for solving the problem of pressure loss in the all-solid-state die battery after external pressurizing equipment is evacuated, so as to ensure that the internal pressure of the die battery finally locked is consistent with the target pressure in assembly. In a first aspect, the present application provides an automated assembly method of an all-solid-state battery test, applied to an automated assembly system of an all-solid-state battery test, the system including a pressurizing unit, an all-solid-state battery die, and a screw locking unit, the method comprising: Controlling a pressurizing unit to apply pressure to an all-solid-state battery die along the axial direction until a target pressure maintaining state is reached, wherein the target pressure maintaining state is a physical state that a solid electrolyte layer in the all-solid-state battery die is compressed to a preset density and the pressurizing unit actively maintains constant pressure; Driving a screw locking unit to screw a fastener into the all-solid-state battery mold in the process of maintaining the target pressure maintaining state, and monitoring an axial load response parameter of the pressurizing unit in real time, wherein the axial load response parameter comprises an output force attenuation amount or a position compensation amount generated by the pressurizing unit for maintaining the target pressure maintaining state; Stopping the screwing action of the screw locking unit when the axial load response parameter is monitored to reach a preset load transfer threshold value, so as to obtain a pressure-locked die assembly, wherein the load transfer threshold value is a critical value interval in which the axial p