Using the BMS to control charging is not considered good engineering practice. The BMS may or may not be designed to operate that way, but once it disconnects the power bus driven by the solar will be at uncontrolled and possibly damaging voltage. Also, different designs of BMS reset (and reconnect) in different ways, and maybe not how you expected.

On Thursday, December 31, 2020 at 3:25:05 PM UTC-8, Eric Greenwell wrote:
Moshe Braner wrote on 12/31/2020 11:12 AM:
On 12/31/2020 12:50 PM, kinsell wrote:

Might want to be careful there. LFP's can be badly damaged when charging under cold conditions.

Good point. "Cold" as in "below freezing" (0C, 32F) for charging, not discharging. It seems
like an arbitrary number (these batteries are not made of water after all) but that's what they
say. I'd recommend at least several degrees above that for charging. If heading into the wave
with an LFP battery, if you have solar charging, you may want to disconnect that (unless the
charge controller does that automatically - do the LFP-aware ones do that?). Would need a
switch for that disconnection. Otherwise it's another reason to avoid solar panels in the
glider, which can't help a lot with the battery running time anyway.
Do some LiFe batteries with a BMS stop charging at a low temperature? If so, maybe that's one
to put in the glider.
--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me)
- "A Guide to Self-Launching Sailplane Operation"
https://sites.google.com/site/motorg...ad-the-guide-1