On Thursday, April 18, 2019 at 11:09:51 PM UTC-4, kinsell wrote:
On 4/17/19 7:58 PM, John DeRosa OHM Ω http://aviation.derosaweb.net wrote:
Luckily with the LiFePO4 batteries when they get below ~11.0Vdc the BMS basically shuts the battery off.
True for most of them, but some of them don't actually do that. Easy to
ruin the battery that way. If I were building a battery tester, I'd
include an automatic load cutoff.
The "B6" device will stop the discharge at 2V per cell. That's only 8 volts for a 4-cell ("12V") battery. That's rather low, although supposedly does not harm the battery. But you can cheat and tell it it's a 5-cell battery, then it will stop at 10V. Just remember to change it to 4 cells for charging!!!
A "12V" LiFePO4 battery in good shape will maintain above or close to 12V for almost all of its discharge curve, then plummet rapidly at the end.