On Monday, March 19, 2018 at 1:37:16 PM UTC-4, Dan Daly wrote:
On Monday, March 19, 2018 at 1:20:31 PM UTC-4, OHM Ω http://aviation.derosaweb.net wrote:
I contacted Bienno for their Lithium Iron Phosphate (LiFePO4) Battery Model BLF-1209WS and they said the following;

The operating temperature is from -20 deg C to 60 deg C (14 deg F to 140 F). Then charge between 0 deg C to 40 deg C (32 F to 104 F)

I left a message for Stark, and will forward the response here.

"Hi Dan,

Both of the charts on the 12V9Ah battery page are based on 1C discharge rates.

With regards to charging below 0C, because the 12V9Ah battery is fairly small, it is always best to charge when it is above 0C. If you have been using the battery and it is just below 0C, your battery will still be above freezing internally and you will be able to charge with you 4A charger without damaging your battery.

Thank you,
StarkPower Customer Care"