Case Study: Rapid State-of-Health (SOH) Estimation of Decommissioned EV Batteries Using ReJoule’s BattScan050M
ReJoule and Renewance collaborated to undertake a comprehensive study on the feasibility of rapidly estimating the state-of-health (SOH) of retired electric vehicle (EV) batteries. This case study provides a concise overview of the results of testing used batteries with ReJoule’s BattScan050M, with the objective to repurpose those batteries into second-life applications like stationary storage systems.
Valence U27-XP LFP module (left), 12.8 V and 138 Ah nominal capacity, connected to the BattScan050M (right).
Methodology:
Batteries and Testing:
1,670 Valence 12.8 V EV battery modules from retired electric delivery trucks.
The BattScan050M device was used to perform Electrochemical Impedance Spectroscopy (EIS) on these modules, estimating their SOH in approximately 5 minutes per module.
Data Storage and Accessibility:
Tests were run through BatteryDB cloud platform. Results can be accessed at any time through the BatteryDB portal.
Tests were run through BatteryDB cloud platform. Results can be accessed at any time through the BatteryDB portal.Scalability and Practicality:
The BattScan050M's portability and ease of use enabled testing at the Renewance warehouse, eliminating the need for costly and time-consuming battery shipping.
This approach allowed a non-certified technician to test up to 45 battery modules per day, significantly increasing throughput and reducing labor costs
Data collected was stored on the BatteryDB cloud platform, enabling scalability and accessibility for analysis and logistical purposes.
Stacks of Valence batteries on pallets stored in Renewance’s warehouse.
3. Environmental and Economic Impact:
Approximately 80% of the battery modules tested were deemed suitable for second-life applications, with an estimated total recoverable energy storage of around 2 MWh (equivalent to over 30 Tesla Model 3s!)
By enabling the rapid identification of batteries suitable for second-life Results:
4. Accuracy and Efficiency:
Renewance was able to grade most of the 1670 batteries in three months. They binned and sorted the batteries by SOH, a process that would have otherwise taken them over a year using cycling.
The median absolute error of the SOH estimation model is 2.9 %, which is comparable to the error metrics of SOH that ReJoule previously deployed for other types of EVs high-capacity batteries.
applications, the BattScan050M helps reduce waste and promotes the reuse of EV batteries.
The project demonstrated the feasibility of creating a domestic supply of reusable batteries, reducing the reliance on new battery production and lowering overall emissions.
ReJoule consistently had >97% accuracy. Even with a test time reduction, in a similar study, ReJoule achieved 98% accuracy with a 6-minute test and 96.5% with a 30-second test.
In conclusion, the BattScan050M has demonstrated its effectiveness in quickly and precisely measuring the SOH of decommissioned EV batteries. This technology not only simplified the process by reducing a year of work into a quarter but also turned unutilized batteries into an asset for Renewance. ReJoule is leading the way in improving battery management methods by greatly decreasing testing time and costs, resulting in increased efficiency and environmental friendliness. For all the detailed information download the conference paper below.
Download the Conference Paper: Rapid Diagnostics To Enable EV Battery Reuse
This Conference paper details ReJoule’s Remade testing project October 1st 2022 to September 30th 2024.
