Charging blocked due to high cell temp?

Yesterday was very hot here in Slovenia. I left home at 37°C drove carefully 140 km and stopped at my father's house with 10% SOC for charging. I plugged in and... nothing happened. Cells temps were between 38 and 42°C. I called Citroen 24/7 assistance... usual story - they have no clue at all. I looked into manual if anything is said about safetytoohightemperaturechargerblocking, but nothing could be found.

It was too hot and too late to wait many hours for battery to cool down, so I ordered insurance assistance and they flat towed me 40 km back home. In my garage I checked cells temps, 35-38°C, plugged in and voila, charging starded.

I suppose BMU just blocks charging if any cell's temp reaches about 40°C. It's a cool feature but not so much this is left out of the manual so the owner can't know what is going on. User manual is very inadequate and sometimes misleading.

I'm sorry if this was discussed already somewhere. I couldn't find it.

First I've heard of this behavior. I'm kind of surprised that it would prevent charging instead of activating the cooling system.

Are you sure there wasn't an issue with the outlet or cord? My brother borrowed my silver car once and called me saying that the car wasn't charging and it was low on charge. Turned out there was no ground connection in the outlet.

PV1 said:

I'm kind of surprised that it would prevent charging instead of activating the cooling system.

Click to expand...

Not all models have a 'cooling system' . . . . or do they?

Don

That's true. Not all have a cooling system. I kind of jumped to the conclusion that all i-MiEVs outside NA had this standard.

Zelenec, do you hear a fan run for roughly 5 seconds when you plug in? Do you have a quick charge port?

That temperatures don't block the i-MiEV to charge, I think. I'm sure, in the past, I had my batteries over 40º C and it allways charged normally.

I-MiEV owers in Australia also see temperatures over 40º C in the battery in summer, they never said anything about no charging at that temperatures.

Usually I hear fan starting right after ch. cable has been plugged in. Red charging light with SOC bars on dashboard come on right on the start of charging. I checked outlet - no problem detected.

Yesterday it happened again. I came home with 37-41°C cells temp. range. Charging didn't start, red charging light starts blinking, bars didn't show. After a few hours I tried again, cells temp 35-38°C. Charging started as usual.

It's really hard to cool down the battery pack at these temperatures. It's the hottest July ever in Slovenia.

All cars sold here (about 40 of them) have Chademo port.

I don't know exactly if there is temp related safety blocking mechanism in my car, but it's the fact I can't charge if any cell goes over 39°C.

I've had a similar experience once recently
It was a hot day 32 C (90 F) and i had just charged L3 and was
driving with full AC on the highway
at 110 km ph (68 mph)
for about 40km (25 miles)
Connected to a level 3and it wouldn't engage the charger

This charger has been known to be troublesome so not sure if it was the BMS
sorry no battery temp info
I charged with a nearby L2 no problem 15 minutes later.

The service manual lists trouble codes that would be stored for various abnormal temperature conditions with the sensors for both the cells and the CMU modules, such as too high, too low or out of range, and indicates the limits as -30 to 60 C. There is also a code for over 115C temperature for the PFC circuit in the onboard charger. So it could be the cells, the monitoring modules or the charger overtemp causing the problem. Pulling the trouble codes would be ideal, but who has a MUT3.

The manual gives items to check: coolant low, water pump failed, radiator fan failed, sensor failed

Keep us posted whatever you find.

I live in Portugal and hot temperatures are common. By these days, temperatures go frequently over 30 ºC by afternoon. Today the maximum will be 29 ºC.

So, my batteries surely went to values over 40 ºC in the past, and that's because, I think, my I-MiEV is the one that shows higher battery degradation. But never had problems in charging, never, and I do it immediately after stopping the car.

In my situation I had just had the 1st annual checkup done and had specifically requested that they check the AC - so I was feeling confident that all was in top shape.