Idle EV info

viatorem replied on 07/03/2023 11:42

viatorem

Posted on 07/03/2023 11:42

Do EV manufacturers give any info on battery charge loss whilst the vehicle is idle? We used to call this quiescent current when I was employed in electronics? The reason I ask is that a neighbour recently returned from a 3 week long haul holiday and found that their parked up EV battery had drained. They had initially travelled the 200 miles or so to the airport and rapid charged the battery before their flight departed planning a swift journey home on returning, the charge costing about £50 (airport prices I guess?). They then had to spend a similar amount on their return which was somewhat annoying after the 15 hr flight. There do seem to be anecdotes on some EV forums regarding idle battery drain. Any EV owners out there know if this is a common issue? Are some manufacturers better than others in this regard?

16 replies

cyberyacht replied on 08/03/2023 08:56

Member

cyberyacht

Motorhomer

Posted on 08/03/2023 08:56

The answer must be to make the roof a solar panel providing a trickle charge to maintain the battery/ residual systems during long periods of idleness.

brue replied on 08/03/2023 09:38

Member

brue

Motorhomer

Posted on 08/03/2023 09:38

Some EVs already have solar roofs. However the point is that they don't normally lose power when parked up.

viatorem replied on 08/03/2023 18:20

Member

viatorem

Posted on 08/03/2023 18:20

Here is the average price for rapid charging from the RAC chargerwatch serviceJanuary

https://www.rac.co.uk/drive/electric-cars/charging/electric-car-public-charging-costs-rac-charge-watch/

so a 100KWhr battery rapid charge could be in the order of £50

Randomcamper replied on 10/03/2023 11:31

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Randomcamper

Motorhomer

Posted on 10/03/2023 11:31

I leave my Skoda Enyaq unplugged for up to two weeks whilst away camping and it does not drop a single percentage point of indicated charge.......

ChocolateTrees replied on 17/03/2023 14:31

Member

ChocolateTrees

Caravanner

Posted on 07/03/2023 19:26 by viatorem

Its a Jag, I don't know if it has a sentry mode. I know that all batteries have a self discharge rate but my understanding is that its around 3% per month for lithium, my guess is that the car may either have a fault or something juicy was running in "standby mode"

A websearch reveals storage procedures for battery cars, quite different advice from some manufacturers. https://www.autovolt-magazine.com/how-to-park-your-ev-for-long-periods-manufacturer-guidance

Posted on 17/03/2023 14:31

Actually, as others have pointed out - there is another major cause of Vampire drain - leaving a regular pre-conditioning timer set. There was an article in the Sun recently about a new EV driver who suffered this on return from Gatwick. It was covered by EVMan on his YouTube channel. Essentially, if you set a timer to have your car all toasty by 8am ready for your commute every weekday, and forget to turn it off when you go on holiday, expect to come back to a car that has drained to the point where it wont run the climate system for a pre-condition. It's very easily done, and if you have an app for your car, easy to turn off too.