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I can't give a definitive answer... I am not an expert on battery tech. But I think it fair to say that there is still a lot of mixed opinions on the 80% vs 100% charging argument so I look at it like this...

As I am still unclear whether charging to 100% regularly is likely to affect the degradation of my battery I work on the principle that I will charge to 80% day to day and charge to 100% when I need to. I never avoid charging to 100% if I need the range... that is what the car is for - to be used. But I cannot see any benefit in taking any unnecessary risks by charging to 100% if I don't need to. It may well turn out that I could have charged to 100% all the time without concern but as I didn't need that extra 20% in the first place then I haven't actually lost out on anything have I?

So my recommendation to all EV owners is, if you are unsure, charge to 100% if you need to but only to 80% if you don't. This is a "just to be on the safe side" approach but doing that will do no harm.

Of course, the caveat of always follow the manufacture's advice applies - (RTFM!), and that includes a 100% charge now and then to balance the cells if the manual says so :)
 

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You start by saying you are not an expert and then you say my advice to ALL ev owners is to...

My advice would be to keep your advice to yourself.
I am no expert on batteries but I am a very experienced EV owner so while I cannot give specific advice about the internal workings of batteries I am very able to offer valuable and sensible advice to people on how to use them.

Why can't you be a nice person and not have a go at people like that unnecessarily?
 

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You are digging the same hole deeper. What makes you think your advice is either sensible or valuable. All you are offering is platidudes based on " what you overheard in the pub". Totally worthless.
You are not only rude but wrong... Best stop digging imo.

How about taking some classes in being friendly... you certainly need them.
 

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The bottom line is just follow the manufacturers instructions. They own the warranty on the battery, have designed the BMS to protect the battery pack and there is absolutely no way they are going to offer that warranty unless they are confident that their instructions are clear and effective. With the sole exception of Tesla, AFAIK, 100% indicated is not actually 100%. The majority of EVs have a buffer, usually around 5%, and during the 20 years or so I've been building battery packs I can say with certainty that a 5% buffer is more than enough to prevent excessive cycle life degradation. Add in that EV batteries just don't get cycled much in their lifetime anyway, and I remain absolutely convinced that there is a massive amount of myth and bullshit being spread around about what owners need to do.

Best advice is just read the manual, follow its instructions and ignore all the crap that's spouted on social media . . .
Totally agree but people don't read the manual most of the time even though they should. My point is that my advice is not bad advice as a starting point regardless of what battery or car you have. There is no risk to charging to 80% ever... but, depending on your battery tech and how your BMS works, there might be a risk to charging regularly to 100%. So my advice works for everyone that doesn't read the manual or who has a car with a rubbish manual that doesn't specify that much detail.
You are digging the same hole deeper. What makes you think your advice is either sensible or valuable. All you are offering is platidudes based on " what you overheard in the pub". Totally worthless.
No platitudes here... just sound advice for anyone as a starting point. Of course, if your manual says something else then do that!

The problem here is that you just hate it when I am right and you will do anything to insult and discredit me. Unfortunately for you all you are doing is making yourself look like the complete ploker that you are. Now ignored (yes... another one :rolleyes: ) so your future comments fall on deaf ears. Have a great day :)
 

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@RobinB So true. Clearly my advice is not any kind of definitive answer to the OP question. Jeremy has the best answer... read the manual. But not all manuals are that detailed and people don't like reading manuals anyway so I chose to give people something they can follow that I know would not be a bad solution if they wanted to follow it.
 

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That's not true, though. If the BMS uses a top balancing system (many do) then doing this will result in the pack gradually drifting out of balance. I've seen this many times over the years.
OK... so clearly you didn't read my caveat in my post...

Of course, the caveat of always follow the manufacture's advice applies - (RTFM!), and that includes a 100% charge now and then to balance the cells if the manual says so :)
I have made the relevant bit easier to read for you.

That both agrees with your first point about follow the manual advice and the point you just made about cell balancing.

Why are people so determined to p**s me off for, what I can see, is no apparent reason?
 

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Sorry, but where exactly is this caveat in the post of yours I quoted, because I can't see it (your snide remark seems to be quoting a different post from the one I quoted and was specifically replying to):



As for me being "determined to p**s me you off" that is simply untrue - you seem to be fond of using inflammatory language, not me.
Read my posts and then your reply makes no sense. I already mentioned about reading the manual and cell balancing... you seem to want to pick a fight over a specific post that doesn't mention that. You aren't Donald in disguise are you? This exactly what I mean... I mentioned the manual... I mentioned cell balancing if the manual says to do it and yet you still want to pick a fight with me. There seems to be no answer to the unfriendly attitude some people have towards me.

I don't, and have never, used inflammatory language except in response to someone being rude or attacking me. If people want to pick a fight then yes, I will fight back, but if people are friendly to me then I am always friendly back. Some people are just not friendly on the forum. I suspect they would be friendly face to face but being online seems to bring out the worst in some people.
 

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Getting back to the topic... my advice IMO works for everyone, regardless of car, regardless of battery. But I say again... my advice is a fallback. Best to read and follow your specific car's manual (as I said) but if the manual is not specific then my advice will do you no harm. I have no idea why some people are against what I say. If they think I am wrong perhaps they could explain why rather than attacking me personally.
 
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