Secondary Battery Activation Aging for Gas Removal and Charge Uniformity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing methods for manufacturing secondary batteries fail to efficiently remove gases remaining in the battery during the activation step, leading to non-uniformity in the battery, which affects the charging uniformity and capacity.
Innovation Solution
A method for manufacturing a secondary battery that involves charging the battery to a low SOC level of 5% to 10%, followed by an aging step at 30-80°C for a predetermined time, and then a second charging step, which includes a pre-aging step, which includes a first charging step of charging the battery to a range of SOC (state-of-charge) of 5% to 10% SOC (state-of-charge) of 30-80°C for a predetermined time, and optionally a second charging step, which includes a pre-aging step, which includes a first charging step of charging the battery to a predetermined SOC (state-of-charge) of 10% to 30-80°C for a predetermined SOC (state-of-charge) of 30-80°C for a predetermined SOC of 5 to less than 10% SOC (state-of-charge) of 30-80°C for a predetermined SOC (state-of-charge) of 0.5 to 10% SOC (state-of-charge) of 0.1 to 1000% SOC (state-of-charge) of 0.1 to 100% SOC.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If the battery is charged to a high SOC level during the activation step, then the charging capacity is increased, but gases remain in the electrode assembly causing non-uniform charging and reduced available capacity
Solution Approach 1:
The charging process is divided into multiple stages: initial charging to a first SOC level (30% or higher), followed by a rest period, then charging to a second SOC level (higher than the first). This segmentation allows gases to be expelled during the rest period between charging stages, preventing gas accumulation and ensuring uniform charging while achieving high overall capacity.
Solution Approach 2:
The method performs preliminary charging to a moderate SOC level (30% or higher) before the final charging stage. This preliminary action generates and expels gases during the intermediate rest period, preventing gas interference in subsequent charging operations and ensuring uniform charge distribution throughout the electrode assembly.
2Productivity
If the battery undergoes conventional activation steps without controlled charging and rest periods, then the process time is reduced, but gases remain in the battery causing electrode degradation and increased defect rate
Solution Approach 1:
The activation process incorporates periodic charging pulses separated by rest periods. The battery is charged to a specific SOC level, then rested to allow gas expansion and expulsion, followed by another charging phase. This periodic action effectively removes gases while maintaining a controlled and efficient process timeline.
Solution Approach 2:
The method dynamically adjusts charging parameters (SOC levels, current rates) and rest period durations based on battery state. By changing these parameters systematically, the process achieves effective gas removal and uniform charging without excessive time consumption, balancing productivity and quality.
3Loss of time
If the battery is charged continuously without rest periods, then the manufacturing time is shortened, but the available capacity is reduced due to gas accumulation and electrode non-uniformity
Solution Approach 1:
The method maintains continuous productive action by structuring rest periods to coincide with gas expansion phases that naturally occur during charging. Rather than idle waiting, these rest periods serve the dual purpose of allowing gas expulsion and preparing the electrode structure for the next charging phase, thus maintaining useful action throughout the process.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This method ensures improved charging uniformity and increased available capacity by removing gases generated during the activation step, reducing the defect generation ratio, and enhancing the yield of the battery.
Implementation Method 1
an aging step of allowing the product of step (S1) to stand under the condition of 30-80°C for a predetermined time
Data Source
Figure 1a~1b
Figure 2a~2b
Figure 3~6
AI summary
Disclosed is a method for manufacturing a secondary battery, including a first charging step to SOC 10% or less and a high-temperature aging step in the battery activation step. In the method for manufacturing a secondary battery, gases generated after the first charging step are removed through the subsequent high-temperature aging step, and thus the electrode shows improved charging uniformity in the subsequent charging step, and the battery shows increased available capacity.