I noticed some strange charging behavior recently. Because I am a terrible procrastinator, I have not yet installed my 6-20 outlet in my garage and am relying on a 5-15 (which gives me 5 rated mph charging).
It's my first winter with the car, so this might be normal behavior. I have charged several times at temperatures in the 20-30°F range. Until today, I got the full 5 mph charge with no battery heating required, even with the blue snowflake icon present. For some reason, my battery has been heating for the last hour when I plugged in this morning (and I've been getting zero miles per hour charge). When I noticed the battery preheating (apparently at a slow rate because I was not losing any rated miles), I preconditioned the cabin manually to try to heat faster. I did this for about 20 minutes. However, the charge rate is still 0mph after over an hour of manual and automatic preheating.
I checked the overnight temperatures, and they were in the mid 20s all night. What gives? Does anyone know what the battery target temperature is for trickle charging? It seems that SMT says the battery target temperature is 50°F right now! I have seen the target temperature jump around a ton in SMT, but does anyone have any good rules of thumb? Heating the battery to 50°F to charge at 12A seems like a giant waste, but maybe I'm missing something. Also, from reading other threads it seems like most people are able to charge at 120V 12A with little to no preheating down to 0-10°F.
I'm not particularly worried about it, but I am curious! I find that my car almost always preheats the battery to charge at 5kW and above, but the preheating for 120V 12A (1.4 kW) charging is new behavior.
It's my first winter with the car, so this might be normal behavior. I have charged several times at temperatures in the 20-30°F range. Until today, I got the full 5 mph charge with no battery heating required, even with the blue snowflake icon present. For some reason, my battery has been heating for the last hour when I plugged in this morning (and I've been getting zero miles per hour charge). When I noticed the battery preheating (apparently at a slow rate because I was not losing any rated miles), I preconditioned the cabin manually to try to heat faster. I did this for about 20 minutes. However, the charge rate is still 0mph after over an hour of manual and automatic preheating.
I checked the overnight temperatures, and they were in the mid 20s all night. What gives? Does anyone know what the battery target temperature is for trickle charging? It seems that SMT says the battery target temperature is 50°F right now! I have seen the target temperature jump around a ton in SMT, but does anyone have any good rules of thumb? Heating the battery to 50°F to charge at 12A seems like a giant waste, but maybe I'm missing something. Also, from reading other threads it seems like most people are able to charge at 120V 12A with little to no preheating down to 0-10°F.
I'm not particularly worried about it, but I am curious! I find that my car almost always preheats the battery to charge at 5kW and above, but the preheating for 120V 12A (1.4 kW) charging is new behavior.