WetEV
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:
viewtopic.php?p=511926#p510938
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.
WetEV
#49
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

Return to “Engineering”