Posts: 1785
Joined: Fri May 04, 2012 8:25 am
Delivery Date: 16 Feb 2014
Location: Near Seattle, WA

CHADEMO based battery testing

Wed Nov 22, 2017 7:58 am

I'm wondering how much market there would be for a CHADEMO based battery testing service.

Thermal soak the car to a known temperature, charge the car to 100%, plug in the tester to the CHADEMO, controlled and measured discharge to a low charge percentage, verify cell voltage balance, and print a nice report.

It seems like this might be valued by a car buyer or seller as the condition of the battery is both important and how to know.

The thermal soak would be required to get a consistent test. Batteries hold more energy at higher temperatures. So put the car into a garage with a big fan moving air over the battery. Could just be controlled temperature air for long enough. Charge to 100% with L2 sometime late in the temperature soak. This process might take a couple of days.

The tester would set up a V2G session at a moderate rate, say 0.4 C, and discharge from 100% to 20% (or something like that). Circuit would include a calibrated voltage and current logger. Probably best to use a measured voltage to set the end of discharge, rather than the car's reported SOC. This process would take a couple of hours. Perhaps something like this:
With a pass through CHADEMO cable with voltage and current monitoring.

The report is "just software" and I can see an ex-boss chucking while I write that, but would be key to the customer.
Most everything around here is wet during the rainy season. And the rainy season is long.
2012 Leaf SL Red (Totaled)
2014 Leaf SL Red

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