Non-aqueous Battery Sealing with Pressure and Segmented Charging
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The manufacturing methods of non-aqueous electrolyte secondary batteries face challenges in reducing the impact of gas on battery characteristics and minimizing the number of times the exterior body needs to be unsealed for gas removal, which can compromise battery performance and safety.
Innovation Solution
A manufacturing method that includes a seal step, a pressure application step, a charge step with two charge phases (first charge to a lower voltage and second charge to full charge without unsealing, and a gas removal step followed by re-sealing, all conducted under decreased pressure to minimize gas influence and reduce the number of unsealing operations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-generated harmful factors
If gas removal step is carried out after the second charge step by unsealing the exterior body, then gas can be removed from the exterior body, but the battery characteristics are reduced due to exposure to moisture and oxygen in the air
Solution Approach 1:
The patent applies preliminary action by performing the gas removal step after the first charge step but before the second charge step. This timing allows gas to be removed when the battery is still relatively stable and before the second charge generates additional gas, thereby reducing the need for unsealing after the second charge and protecting battery characteristics from exposure to air.
Solution Approach 2:
The patent maintains continuity of useful action by keeping the exterior body sealed throughout the entire manufacturing process except during the specific gas removal window between first and second charge steps. This continuous sealing approach minimizes exposure to air and maintains battery characteristics while still allowing necessary gas removal.
2Object-generated harmful factors
If the exterior body is unsealed multiple times for gas removal, then gas can be removed effectively, but the safety and manufacturing complexity increase
Solution Approach 1:
The patent performs gas removal as a preliminary action between the first and second charge steps, addressing gas accumulation before it becomes a critical issue. This single timing for gas removal minimizes the number of unsealing operations while still effectively managing gas, thereby reducing manufacturing complexity and safety risks.
3Reliability
If the first charge step is carried out after sealing the exterior body, then battery safety is improved, but gas generated during charging cannot be removed
Solution Approach 1:
The patent segments the charging process into two distinct charge steps with a gas removal step in between. The first charge step is performed with the exterior body sealed to ensure safety, then gas is removed, and the second charge step completes the charging process. This segmentation allows both safety and gas management to be achieved.
Solution Approach 2:
The patent maintains continuous sealing of the exterior body throughout the charging process except for the brief gas removal interval. This approach preserves battery safety by minimizing exposure to air while still allowing gas to be removed through the controlled unsealing between charge steps.
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 effectively reduces the number of gas removal steps and suppresses the negative impact of gas on battery characteristics, enhancing battery performance and safety by allowing gas to be managed within the battery structure without frequent unsealing.
Implementation Method 1
a pressure application step of applying a pressure on the exterior body in which the electrode laminate is stored
Implementation Method 2
gas is generated in association with a reaction of the electrolyte
Data Source
Figure 1(a)~1(b)
Figure 2
Figure 3
AI summary
According to the present invention, there is provided a seal step (ST105) storing an electrode laminate in which a separator is disposed between a positive electrode and a negative electrode and an electrolyte within an exterior body constituted by a laminate film and sealing the exterior body; a pressure application step (ST106) of applying a pressure to the exterior body in which the electrode laminate is stored by means of a flat plate press working or so forth; charge step (ST102) of charging up to a full charge; a gas removal step (ST107) of unsealing the exterior body and removing gas generated within the exterior body at the charge step; and a re-seal step (ST108) of sealing the exterior body after the gas removal step. The number of times of the gas removal steps is small and an influence of gas on battery characteristics is suppressed.