Water-Responsive Safety Layer for Button Cell Battery Protection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Small button cell batteries, especially coin cells, pose a risk of tissue damage and electrolysis when swallowed due to their size and chemistry, which can lead to bodily harm and burns, as they can become lodged in the throat and react with body fluids.
Innovation Solution
A composite water-responsive safety layer is integrated into the battery cells, comprising a polymer matrix with a metal salt and metal powder, which transitions from a non-conducting to a conducting state when exposed to aqueous solutions, creating a short circuit to reduce voltage below harmful levels, thereby preventing electrolysis and tissue damage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If button cell batteries are made small for portability, then ease of operation and compactness are improved, but the risk of tissue damage and electrolysis when swallowed increases
Solution Approach 1:
The patent applies preliminary action by incorporating a safety layer that proactively responds to aqueous environments before harmful electrolysis can occur. The safety layer contains reactive materials that immediately neutralize water upon contact, preventing the formation of harmful hydroxide ions and hydrogen gas that would otherwise cause tissue damage during battery ingestion
Solution Approach 2:
The patent converts the harmful reaction between battery materials and body fluids into a beneficial protective mechanism. The safety layer uses controlled chemical reactions with water to generate a protective barrier or neutralizing agents that prevent the dangerous electrolysis of body fluids, thereby transforming the potentially harmful electrochemical activity into a protective function
2Reliability
If a safety layer is added to prevent tissue damage, then safety is improved, but device complexity increases
Solution Approach 1:
The patent merges the safety function directly into the battery structure by integrating the safety layer as an inherent component during battery manufacturing. The safety layer is combined with the battery housing or electrode structures, creating a unified design where safety functionality is built-in rather than added as a separate external component, thereby minimizing structural complexity
Solution Approach 2:
The patent employs a thin-film safety layer that can be applied as a coating on battery components. This flexible, thin-film approach provides comprehensive safety coverage across the battery surface without adding significant bulk or structural complexity, maintaining the compact form factor while delivering protective functionality
3Reliability
If the battery is designed to short-circuit in water, then safety is improved, but normal battery performance may be affected
Solution Approach 1:
The patent applies dynamics by designing a safety system that adaptively changes the battery's electrical characteristics based on environmental conditions. The safety layer remains electrically inert during normal dry operation, allowing full battery performance, but dynamically activates to create a short-circuit pathway when exposed to aqueous environments, thereby providing condition-dependent protection without compromising normal functionality
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
The safety layer effectively shortens the battery voltage to non-threatening levels when exposed to saliva or stomach fluids, preventing electrolysis and reducing the risk of burns, while maintaining normal performance under regular conditions and storage in humid environments.
Implementation Method 1
A composite water-responsive safety layer is integrated into the battery cells, comprising a polymer matrix with a metal salt and metal powder, which transitions from a non-conducting to a conducting state when exposed to aqueous solutions
Implementation Method 2
creating a short circuit to reduce voltage below harmful levels, thereby preventing electrolysis and tissue damage
Data Source
Figure 1
Figure 2A~2B
Figure 3~4
AI summary
A battery cell comprising a composite water-responsive safety layer and/or composite water- and pH-responsive safety layer to protect against tissue damage and/or electrolysis, when the battery cell is exposed to aqueous solution or tissue, is provided.