Battery System Upper-Limit Electrical Quantity Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional battery systems fail to effectively prevent the deterioration of secondary batteries, leading to increased weight and cost due to excessive battery capacity, and may not ensure a sufficient electrical quantity for a predetermined period, resulting in reduced travelable distance in battery-equipped vehicles.
Innovation Solution
A battery system with an upper-limit electrical quantity setting means that sets a limit below the full charge state, gradually decreasing as the battery deteriorates, and a charging means that charges the battery up to this limit, ensuring a stable and sufficient electrical quantity over time.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If the battery is charged to full charge state in every charging, then the electrical quantity obtainable from the battery is maximized, but the deterioration of the battery accelerates
Solution Approach 1:
The patent applies partial action by charging the battery only to an upper-limit electrical quantity that is less than the full charge state. The upper-limit electrical quantity is set to a value that provides a predetermined margin (e.g., 80-90% of full charge) to prevent excessive charging that causes rapid deterioration. This partial charging approach balances electrical quantity availability with battery life extension.
Solution Approach 2:
The patent implements dynamics by making the upper-limit electrical quantity adjustable based on the deterioration state of the battery. As the battery deteriorates over time, the upper-limit electrical quantity is dynamically revised to an even lower value. This dynamic adjustment ensures that the battery is never charged to a level that would cause rapid deterioration, while still maximizing the usable electrical quantity at each stage of the battery's life.
2Reliability
If the initial battery capacity is increased to account for deterioration, then the warranted electrical quantity can be maintained, but the vehicle weight and cost increase
Solution Approach 1:
The patent applies preliminary action by proactively managing the upper-limit electrical quantity based on predicted future deterioration. Instead of increasing initial battery capacity to compensate for future losses, the system pre-establishes a charging strategy that prevents rapid deterioration from the outset. By charging to a lower upper-limit electrical quantity from the beginning and adjusting it dynamically as deterioration progresses, the system maintains the warranted electrical quantity without requiring excessive initial capacity, thereby avoiding increased vehicle weight.
3Device complexity
If the upper-limit electrical quantity is set to a fixed value, then the charging control is simple, but the electrical quantity may become insufficient as the battery deteriorates
Solution Approach 1:
The patent implements feedback by continuously monitoring the deterioration state of the battery and using this information to dynamically adjust the upper-limit electrical quantity. The system receives input about the battery's current state (through voltage, current, temperature measurements and historical data) and automatically revises the upper-limit electrical quantity accordingly. This feedback mechanism ensures that the electrical quantity remains sufficient throughout the battery's life without requiring complex manual intervention or fixed conservative limits.
Data Source
AI summary
A battery system 100 includes an upper-limit electrical quantity setting means (an ECU 120) for setting an upper limit of an electrical quantity (an upper-limit electrical quantity Da) obtainable from a battery pack 110 to a lower value than in a full charge state. This upper-limit electrical quantity setting means 120 sets the upper-limit electrical quantity Da to a value having a difference from the electrical quantity (a full-charge electrical quantity Dmax) obtainable from the full charge state so that the difference is smaller as the deterioration of the battery pack 110 progresses. Further, the battery system 100 includes a charging means (the ECU 120) for charging the battery pack 110 under the condition that the upper-limit electrical quantity Da is an upper limit.