How to Grade Used Batteries for a Second Life

This patent describes a system that reads electrical characteristics and usage history from a rechargeable battery module to determine if it's good enough to be used again for a different purpose, like energy storage.

What it covers

This patent describes a system for managing rechargeable batteries, called 'secondary battery modules.' Each battery module stores its own 'electrical characteristic information' (like its original capacity and how much it resists current) and 'usage history information' (like its voltage and current ranges over time) (Claim 1). A 'battery information management device' connects to these modules, reads this stored data, and then compares it to a 'predetermined threshold' (Claim 1). If the battery's information meets the threshold, the device 'grades' it as suitable for 'reuse,' meaning it can be used for something else after its first life, perhaps in an electric vehicle (Claim 1). For example, a device could read data from an old electric car battery, see its remaining capacity is above a certain level, and then grade it for use in a home solar power storage system.

What it doesn't cover

• —Does not cover managing primary (single-use) batteries, only 'secondary battery modules' that are rechargeable.
• —Does not cover battery management systems that only monitor battery health without explicitly grading for 'reuse' based on predetermined thresholds.
• —Does not cover systems where battery characteristic and usage history information is not stored directly within the 'secondary battery module' itself.
• —Does not cover grading systems that do not use specific 'electrical characteristic information' and 'usage history information' as claimed.
• —Does not cover systems that simply charge or discharge batteries without reading and grading their internal information for reuse.

The clever bit

The clever part is combining on-board storage of detailed battery history with a centralized system that specifically grades these batteries for 'reuse' against predefined limits. This allows for an automated and standardized way to assess a battery's suitability for a second life, rather than just discarding it.

Why it matters

As electric vehicles become more common, there will be a growing number of used EV batteries. This patent addresses the challenge of figuring out which of these batteries still have enough life left to be repurposed for other uses, like storing energy from solar panels or powering homes. By providing a structured way to assess battery health for reuse, it supports the development of a 'second-life' battery market, reducing waste and making better use of valuable resources.

Real-world examples

• 1.Nissan LEAF second-life battery projects
• 2.Tesla Powerwall (though not necessarily using this patent, it represents the market for repurposed batteries)
• 3.Energy storage systems for commercial buildings using retired EV batteries
• 4.Grid-scale battery storage solutions