Charging and conditioning (warming) the battery

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Kristian

Active member
Joined
Apr 23, 2018
Messages
32
Location
Wiltshire, England
Hi,

I have a 90Ah BEV.
At home I only have a slow charger (10amp @ 240v).
What takes priority when the car is plugged into a slow charger? Charging or Conditioning?

So as an example, lets say I plan to leave in 3.5 hours and the battery is half charged, so set the schedule up for that so that the battery can be warmed up (AKA conditioning) for when I leave.
So, for the 1st 30 minutes, I'm guessing the all the power from the charger will go to charging the battery.
After that, will some or all the power go to warming the battery?
Is there any way to only warm the battery, but not charge it? (I get free charging at work, so would like to take full use of this, but also keep the battery in the best long term health possible).

From what I've read here and elsewhere I know the cabin heater can draw from the battery even when plugged into a charger.

Many Thanks

Kristian
 
The battery warming is a 1Kw heater. If the batteries are cold enough to benefit from that, that amount of power will go towards that function and any of the remaining will eventually end up helping to condition the cabin, if you've selected that option for the last 30-minutes or so prior to your stated departure time. Under the worst case scenario, battery conditioning might start 3.5-hr before your departure time, less, if the batteries aren't super cold. There's a lot of mass to heat up, and the heater isn't huge, so it takes time.

240*10=2400W available, assuming your supply actually is 240vac. At a peak, I've seen my car drawing twice that amount, which means potentially not leaving with a full battery as the car will try to use more than is being put into it from the EVSE.

I do not know how or if the car tries to balance warming the batteries verses charging them verses trying to ensure you have maximum range available when you say you want to leave.
 
Thanks for the reply.
As long as I have 50% charge when leaving for work (28 miles each way) then I'm happy. As we are in the middle of a heatwave I'm not plugging the car in at all when I get home.
 
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