Power Tool Battery Pack Sealing Against Moisture Short Circuits
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Battery packs in power tools experience short circuits due to moisture or water exposure leading to hydrolysis reactions and heat generation, which can increase temperature and pose safety risks.
Innovation Solution
The battery pack design includes a cell unit with a sealing ring and partition made of materials like hard film rust preventive oil or fluororubber, and a surfactant applied to charged surfaces to prevent short circuits by increasing insulation and blocking air communication paths between positive and negative electrodes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If multiple cell units are arranged in a battery pack with positive and negative electrodes close to each other, then the battery pack achieves compact design and high energy density, but moisture or water exposure causes short circuits and hydrolysis reactions leading to heat generation and temperature increase
Solution Approach 1:
The patent introduces an insulating film as an intermediary layer between the positive and negative electrodes. This film acts as a mediator that prevents direct contact and electrical conduction between the electrodes, while still allowing the battery pack to maintain a compact design. The insulating film specifically blocks moisture and water pathways that would otherwise cause short circuits and hydrolysis reactions.
Solution Approach 2:
The patent applies insulating treatment to critical surfaces and pathways where moisture accumulation occurs. By skipping the need for larger physical separation distances, the insulating treatment allows the battery pack to maintain compact dimensions while still preventing moisture-induced short circuits through chemical or physical barrier properties.
2Quantity of substance
If the positive and negative electrodes are positioned close together for compact design, then energy density is improved, but the risk of short circuits due to moisture exposure increases
Solution Approach 1:
The patent employs thin film insulating coatings on electrode surfaces and in critical pathways. These flexible thin films conform to the electrode geometries and provide continuous moisture barriers without requiring significant increases in battery pack volume, thus preserving energy density while protecting against moisture exposure.
Solution Approach 2:
The patent uses composite insulating structures combining multiple materials with different properties. For example, hydrophobic coatings combined with physical barriers create a multi-layer protection system that effectively blocks moisture while maintaining the compact electrode arrangement needed for high energy density.
3Reliability
If insulating treatment is applied to charged surfaces using surfactant, then short circuit prevention is improved, but the complexity of manufacturing process increases
Solution Approach 1:
The patent employs surfactant-based insulating treatments that can be applied through immersion or vapor deposition methods. These treatments utilize the self-assembling properties of surfactants to form uniform insulating films on charged surfaces without requiring complex application equipment or multiple processing steps, thus improving reliability while keeping manufacturing relatively simple.
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 solution effectively prevents short circuits and improves insulation, ensuring safe and reliable operation of power tools by minimizing creepage and short circuit risks in humid environments.
Implementation Method 1
A cell unit of the at least one cell unit includes at least one charged surface to which a surfactant is attached
Implementation Method 2
The sealing ring is formed with or connected to a partition, and the partition is connected to at least the positive electrode assembly and the negative electrode assembly
Data Source
AI summary
A battery pack is configured to power a power tool and a charging combination. The battery pack includes a housing; and a cell assembly disposed in the housing and including at least one cell unit; where a cell unit of the at least one cell unit includes at least one charged surface to which a surfactant is attached. According to the above technical solutions, the battery pack can have good insulation, a strong anti-rust ability, and high safety performance between a positive electrode and a negative electrode.