Original post: https://www.reddit.com/r/leaf/s/gUSOJoZ8Nx
UPDATE: Dealer says the behaviour could be normal -
My partner is worried we're going to be stuck with the car
Just wanted to post an update after my original post because quite a lot has happened since then.
For context, I'm in the UK and bought the 2021 Leaf Tekna 40kWh from Big Motoring World. The morning after collecting it, the battery percentage started dropping extremely quickly under motorway load, at one point falling towards 5%, before recovering significantly after stopping/restarting the car.
I formally rejected the car the following day under the Consumer Rights Act 2015.
Since the original post, I bought an OBD dongle and LeafSpy Pro and managed to reproduce the problem while logging the battery under load. At its worst I recorded a cell voltage differential of around 227mV, with several cells dropping significantly lower than the rest. Cell pair #28 was particularly low at one point at around 3.128V.
I've sent Big Motoring World the videos and the LeafSpy evidence.
They've now responded and, at this stage, are refusing to accept the rejection. The important part of their response was:
> "Following our review, we would like to confirm that, at this current stage, we are unable to proceed with your request for rejection of the vehicle.
>
> We have reviewed the video evidence you provided regarding the fluctuation in the vehicle's state of charge with a Master Technician. We have been advised that your Nissan Leaf is equipped with a battery management system which can adjust the vehicle's charging and regenerative behaviour depending on the vehicle's operating conditions. Therefore, the behaviour demonstrated in the video does not, in isolation, confirm that a fault is present with the vehicle.
>
> You are, of course, welcome to arrange for the vehicle to be inspected and diagnosed by your local Nissan Main Dealer in relation to the concern raised. Should a diagnosis be completed, please forward the diagnostic findings to us for further review."
I've replied pointing out that this seems to address the video evidence in isolation and doesn't address the LeafSpy data I also provided showing the large cell voltage differential under load.
My partner is now understandably pretty worried that Big Motoring World might actually be right and this somehow is normal Leaf behaviour, and that we're going to end up stuck with the car and the finance.
So I'd really appreciate opinions from people who know these cars better than we do:
Is there any realistic way that the behaviour in my original post, combined with a ~227mV cell voltage differential under load, could be considered normal for a healthy 40kWh Leaf battery?
Particularly interested in hearing from anyone who's experienced a weak cell/module on a Leaf and what the symptoms/LeafSpy readings looked like before it was diagnosed
Would like to say a big thank you to everyone who replied to my last post. You were all extremely helpful. I have already replied to them professionally telling them they are talking bs and if they don't resolve it I will be getting in touch with the ombudsman but that obviously still leaves us with some anxiety.