Parallel Battery Pack Control for Alternating Charge-Discharge
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Batteries using lithium metal as the negative electrode deteriorate prematurely when discharged at low rates, and when charged at high rates, necessitating a solution that balances discharge and charge rates to prevent premature degradation.
Innovation Solution
A management system that alternately discharges and charges multiple battery packs, controlling the discharge rate and voltage differences between packs to maintain optimal conditions, using a management device to regulate the connection of battery packs to a bus and power generation units, and managing power distribution to loads.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Duration of action of moving object
If lithium metal batteries are discharged at low rates, then the discharge rate is controlled to extend lifespan, but the battery deteriorates prematurely
Solution Approach 1:
The patent implements periodic alternation between discharge and charge operations for battery packs. Multiple battery packs are cycled through discharge and charge phases in sequence, ensuring that no single battery undergoes continuous low-rate discharge or high-rate charging. This periodic switching resolves the contradiction by preventing premature deterioration while maintaining required discharge rates.
Solution Approach 2:
The system dynamically changes operational parameters by switching which battery packs are in discharge mode versus charge mode. The management device monitors state of charge, discharge rate, and charge rate parameters, adjusting the operational state of each battery pack to maintain optimal conditions. This parameter management prevents both low-rate discharge deterioration and high-rate charging damage.
2Productivity
If lithium metal batteries are charged at high rates, then the charge rate is increased to improve efficiency, but the battery deteriorates prematurely
Solution Approach 1:
The system uses periodic action by alternating battery packs between charge and discharge modes. When one battery pack is charging at high rate, another is discharging, and vice versa. This periodic switching ensures that no single battery experiences continuous high-rate charging, thereby preventing deterioration while maintaining overall system charging efficiency.
Solution Approach 2:
The patent segments the battery system into multiple independent battery packs, each capable of independent charge/discharge operation. This segmentation allows the management device to distribute charging loads across multiple packs, preventing any single pack from undergoing excessive high-rate charging that would cause deterioration.
3Duration of action of moving object
If multiple battery packs are used with alternating discharge and charge, then battery lifespan is extended, but system complexity increases
Solution Approach 1:
Each battery pack in the system is designed with universal functionality, capable of both discharge and charge operations. This multi-functionality reduces system complexity because all battery packs follow the same operational protocol and can be managed by a single control algorithm, rather than requiring different management strategies for different battery types or roles.
Solution Approach 2:
The management device uses standardized parameter monitoring and control across all battery packs, tracking state of charge, voltage, and current parameters uniformly. This consistent parameter management approach simplifies the control logic despite having multiple battery packs, as the same algorithms apply to each pack regardless of its current operational state.
Data Source
AI summary
Provided is a system comprising: a management unit that manages a plurality of battery packs, which are connected in parallel to a bus to which a power generation unit and a load are connected, to have the plurality of battery packs being alternately discharged so that a voltage difference between a battery pack with a highest voltage and a battery pack with a lowest voltage among the plurality of battery packs is not greater than a voltage threshold.