Wound Battery Insulator Tape Placement for Short Circuit Prevention
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Solution Overview
Problem
Conventional lithium ion batteries face safety issues due to short circuits caused by the non-coating parts of electrodes coming into contact, leading to inadequate electrical insulation and potential heat emission.
Innovation Solution
The cathode and anode leads are arranged in opposite directions, and insulator tapes are strategically attached to the boundaries of the cathode active-material coating layers where they face non-coating parts, preventing short circuits and enhancing electrical insulation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If insulator tapes are attached to prevent short circuits between non-coating parts and active-material coating layers, then electrical insulation capability is improved, but device complexity increases
Solution Approach 1:
The patent applies insulator tapes specifically at the boundary between the cathode active-material coating layer and cathode uncoated part where the anode active-material coating layer faces. This localized application provides electrical insulation exactly where needed (at the short-circuit risk boundary) without adding insulators throughout the entire electrode structure, thus improving reliability while minimizing added complexity
Solution Approach 2:
The insulator tape acts as an intermediary element between the cathode active-material coating layer and the anode active-material coating layer. This thin insulating layer prevents direct contact and potential short circuits between the two active materials, while maintaining the compact wound structure of the battery
2Reliability
If cathode and anode leads are arranged in opposite directions to prevent short circuits, then safety is improved, but ease of operation deteriorates
Solution Approach 1:
The patent arranges the cathode lead and anode lead in opposite directions rather than symmetrically adjacent to each other. This asymmetric arrangement ensures that the non-coating parts of the electrodes do not face each other, preventing short circuits and improving safety, though it requires more careful positioning during assembly
Data Source
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AI summary
Disclosed is a battery including a cathode and an anode wound to face each other with a separator interposed therebetween. Both surfaces of a cathode collector are provided with cathode active-material coating layers so as not to provide a cathode uncoated part at a winding beginning portion of the cathode. The cathode uncoated part for installation of a cathode lead is provided only at a winding ending portion of the cathode. An insulator tape is attached to the boundary of the cathode active-material coating layer facing the anode at the winding ending portion of the cathode. Providing the insulator tape to the boundary of the cathode active-material coating layer at a position where a non-coating part not containing the cathode active-material coating layer and an anode active-material coating layer face each other achieves enhanced electrical insulation capability and consequential safety of the battery.