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Re: Battery management cooling when stationary and not plugged in to a charger

Posted: Thu Nov 19, 2020 5:34 pm
by keithr
SwissChris wrote: Thu Nov 19, 2020 3:10 pm The question is: If you preset the heating at a certain time - will the car then also pre-condition the battery? ;)
I would say, no. It will warm the battery while charging, but it won't warm the battery if not charging and the car is not turned on (third row, second column in the table). The car's pre-conditioning climate schedule works independently of whether the car is plugged in to a charge point or not.

I would like to see the follow-up article to that EEWORLD web page, as it said it would next look at the Honda's battery cooling processes. However, I struggled to search for it because it's all in Chinese!

Re: Battery management cooling when stationary and not plugged in to a charger

Posted: Thu Nov 19, 2020 8:45 pm
by Trykpaa
advance2020 wrote: Thu Nov 19, 2020 4:46 pm A coincidence, but I went out for a short drive today and decided to charge my battery for an hour or so prior. It seemed that I got slightly better economy on this very short journey. AVG was 3.3 rather than 3.0 that I have been getting lately. I had assumed this was because my battery was warmed up.
I will try this again in future (cold weather) prior to short trips as I'm on a Fixed Tariff, and have no Smart meter.
My wife consistently also gets at least as good or better energy efficiency when preheating - even when preheat without being plugged in. It seems odd to me, but the stats speaks for them selves.

Re: Battery management cooling when stationary and not plugged in to a charger

Posted: Fri Nov 20, 2020 1:48 pm
by keithr
Trykpaa wrote: Thu Nov 19, 2020 8:45 pm My wife consistently also gets at least as good or better energy efficiency when preheating - even when preheat without being plugged in. It seems odd to me, but the stats speaks for them selves.
I would presume that is because she is then not needing to use the heater as much when driving. That's the main reason for pre-heating, to save using battery charge on heating, and therefore decreasing the range, by heating before driving using electricity from the charge point. The car should warm up much more quickly when starting to drive than an ICE car, because it doesn't have to wait for the engine to heat up, so pre-heating just for comfort doesn't seem to be of much value to me. Perhaps in very cold climates it might be a nice option, or perhaps people are becoming too soft!

Re: Battery management cooling when stationary and not plugged in to a charger

Posted: Fri Nov 20, 2020 9:23 pm
by CSX
Great insights - really helpful. If you set the climate to come on it will be drawing power and heat up the battery anyway but it would make sense that it actively pre-conditions it to the optimal operating temperature.

Re: Battery management cooling when stationary and not plugged in to a charger

Posted: Sat Nov 21, 2020 1:24 pm
by keithr
CSX wrote: Fri Nov 20, 2020 9:23 pm If you set the climate to come on it will be drawing power and heat up the battery anyway
The heater wouldn't draw as much power as driving the car would (I'd estimate about 5% of the consumption of driving), and it would probably have a negligible battery warming effect.

BTW, the heating of the battery in the "battery over-cooled protection" mode (plugged in but not charging) is only designed for protecting the battery from damage. I haven't seen any figures for the Honda e, but for the Nissan LEAF they fit a battery heater in cold climate countries, and that heater only turns on when the battery temperature drops to -17C and turns off when it has warmed up to -10C. I would guess it's similar for the Honda, so the battery will still be very cold. It will only warm the battery up to to the optimum 25C if it is also charging because a cold battery can't be charged as quickly (see the blue line in the 'Battery warm-up during charging' graph above) and it will not be able to hold as much charge as a warm battery. I'm not sure if the charge limit will be reached while AC charging a cold battery at 6.6kW in the UK (usually above freezing temperatures), perhaps it would only reduce the charge rate when rapid charging a cold battery.

Re: Battery management cooling when stationary and not plugged in to a charger

Posted: Sat Nov 21, 2020 7:54 pm
by CSX
Fair point Keithr- think you’re right probably wouldn’t heat it up that much

Re: Battery management cooling when stationary and not plugged in to a charger

Posted: Mon Nov 30, 2020 1:11 pm
by volkerb
keithr wrote: Thu Nov 19, 2020 5:34 pm
SwissChris wrote: Thu Nov 19, 2020 3:10 pm The question is: If you preset the heating at a certain time - will the car then also pre-condition the battery? ;)
I would say, no. It will warm the battery while charging, but it won't warm the battery if not charging and the car is not turned on (third row, second column in the table). The car's pre-conditioning climate schedule works independently of whether the car is plugged in to a charge point or not.

I would like to see the follow-up article to that EEWORLD web page, as it said it would next look at the Honda's battery cooling processes. However, I struggled to search for it because it's all in Chinese!
Strange difference between the German and UK manual (Page 381):

UK:
If the temperature of the High Voltage battery drops to -30°C or below, the power system will not start. Wait for the High Voltage battery to warm up or move the vehicle to a warmer location. Note using the battery heating system will not help in this case

German (my translation attempt ;)):
If the temperature of the High Voltage battery drops to -30°C or below, the power system will possibly not start. Wait for the High Voltage battery to warm up. With climate control switched on, the heating system of the battery will be activated.

If the temperature of the High Voltage battery drops to -35°C or below, the power system will not start. Wait for the High Voltage battery to warm up or move the vehicle to a warmer location. Note using the battery heating system will not help in this case

Different handling of battery pre-conditioning or simply faulty manuals? Pre-conditioning with preset heating or only below -30°C? :?

Re: Battery management cooling when stationary and not plugged in to a charger

Posted: Mon Nov 30, 2020 1:34 pm
by iHansz
Funny!

Dutch manual:

If the temperature of the high voltage battery drops to -30 °C or below, the power system may not start. Wait for the high voltage battery to warm up. When climate preconditioning is on, the battery heating system is activated.

If the battery temperature drops to -35 °C or below, the power system will not start. Wait for the high voltage battery to warm up or move the vehicle to a warmer location. Note: using the battery heating system is pointless in this case. Store the vehicle in a garage or take some other measure to make sure that the temperature of the high voltage battery does not drop below this temperature. If necessary, contact a dealer.

Re: Battery management cooling when stationary and not plugged in to a charger

Posted: Mon Nov 30, 2020 1:45 pm
by volkerb
OK - Netherlands closer to Germany :lol:
I would love this sentence to be true in every case: "When climate preconditioning is on, the battery heating system is activated."