Timed charging of my I3

BMW i3 Forum

Help Support BMW i3 Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Though not 'smart' in terms of coordinating automatically with TOU variations, EnelX Juicebox chargers allow scheduled charging. They are too expensive in my opinion vs. the cheaper charger I got off of Amazon if TOU is not a concern, but I was given one recently, and it's a nice upgrade for that, as well tracking charge status and energy consumption. I don't see a way to regulate charge percentage, but I think we have sufficiently shown that's not really something to be concerned with for the i3.
Batt. Kappa. max varied ±2 kWh in our former 2014 i3 over a period of a few weeks, so I don't consider it to be very meaningful. I didn't attempt to read Batt. Kappa. max under similar conditions which might have affected its readings. For several months, it was an unrealistically high 20+ kWh for a battery pack whose new nominal usable capacity was 18.8 kWh. It is a calculated estimate of the maximum usable capacity, but we don't know how this calculation is made and what affects the calculation.

The capacity of a battery cell depends on the charging or discharging power under which the capacity was measured, the cell's temperature, and maybe other factors, so there's not a single correct usable capacity.
Yes I'd heard that it is not a fixed point reading ... bit like the predicted range I guess? ... but it has never varied by that much.
If I were to do a graph it would be a jagged line (+/- 0.4) with a steady upward trend starting after four months.
Would be interesting to see how it matches to ambient outside temp across the year maybe, since this winter was milder here than last.
If it had been as cold maybe the figures would have reverted to what they were like in the first four months (Oct to Jan).
I'll keep checking in on it for the longer picture......
... Juicebox chargers allow scheduled charging. They are too expensive in my opinion ... I don't see a way to regulate charge percentage
Yeah, no smart charger is going to do that unless it has some sort of end-around method to monitor the app API, since there's no state of charge data being shared over the J1772 connection.

I bought a $200 ZenCar unit that allows me to easily select 16/12/10/8/6 amps, and 2/4/6/8 delayed starts. Because I charge most days on a 120 volt outlet at work this is great, and it also works with the 240 volt receptacle at home (despite me also having a 40 amp Clipper Creek we plug into the other car).

Point is, I can easily manually limit myself to ~80% because the AC charging curve is linear. I know that over an 8 hour workday I get 30% charge at 16 amps, 22% at 12 amps, 17% at 10 amps, etc. and I can just swipe the start timer to put the whole thing on ice.

I'd much rather have the car manage this cutoff for me, but whatevs... this adaptation works well enough to keep my battery in my preferred sweet spot most of the time.
Hi Everyone.....I am in the UK. My first i3 was bought in 2014 had a timing fault and the dealership corrected this. My second i3, bought under warranty in 2022 has the identical fault (inability to stop charge on timer) and the dealer will not fix this. I use Octopus Agile which means I am PAID to use electricity in 30 minute aliquots (please see attached). I have now taken the dealer to the Motor Ombudsman to either 'fix;' the issue or recognise the inconvenience it causes the consumer. Case still pending.Screenshot_20230927_103139_Octopus Watch.jpg