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Discussion Starter #1
Hi All

New to forum but have been reading up a bit over the last few weeks.

Am looking at a Leaf 24 with the 6.6kw charger. This works well for me as i will be able to charge fully overnight during the 4 hour cheap period offered by Octopus. Will also be able to top up a little quicker at 7kw chargers out and about. So it seems that there are some clear upsides but are there any downsides ? I did see a bit of a debate on one thread about possible detrimental affects on battery albeit this didn't seem to be backed up by anything other than an off hand comment by an ev specialist dealer.

Thanks for any advice you can offer.

E
 

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Very much doubt that 6.6kW charging would be a problem for the battery.
Only possible "downside" I can see is the higher draw on your home electrics, and charging "too quickly" if you have PV panels and want to try and charge on your own electricity - I don't think there's a way to "step down" the 32A charger to 16A or less - other than using a 16A rated cable or charger, perhaps.
 

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At nearly six years old and 86k miles, our Leaf 24kWh with 6.6kW charger still has 11 out of 12 battery bars and battery health seems pretty stable (fingers crossed). The 6.6kW charger was quite an expensive option but just makes the car so much more usable for us when we often have multiple longer journeys in a day (i.e. 50% charge in 2 hours rather than 4 hours), meaning we have to use our PHEV far less. A bigger battery BEV would obviously be ideal one day, but for me there are only pluses to having the 6.6kW charger.

I suspect that charging at the higher rate for so long has minimal real world impact on the battery as long as you take care of it (i.e. avoiding mistreating the battery by leaving it at 100% for long periods, charging from high state-of-charge, etc.).
 

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I've just bought a 2nd hand leaf 2 weeks ago and went for the 6.6kW charger as a must.

I'm not able to charge at home so am dependent on charge points at work and ones in local supermarkets (both Pod-point). As the supermarket ones are currently free I figured that on average, 4 hours a week at 6.6kW would actually keep me topped up, so a 1 or 2 hour visit to the supermarket and the rest at work (which are a very reasonable 12p/kWh).

There is a bit of literature (*) around that suggests that the best charging rate is actually more than the 6kW rate, so I wouldnt worry too much about that perspective. I agree with other posters that there are much bigger factors than charge rate that would be detrimental to the battery, e.g charging to 100% regularly and leaving it there etc. As the leaf has a charge timer setting built in you can set it to charge for a limited period so the faster rate doesnt mean you lose control of the choice of how much charge you want to put it at any one time. The only disadvantage I saw is that the 6.6kW cars come at a price premium.

I should point out that my leaf came with TWO cables. One is a straight point to point cable for connecting to public charge points - this allows charging at the 6.6kW rate. The 2nd is a cable that has a 3 pin plug on it, which will charge at 3kWish (as 240V x 13A = 3.12kW). So you if you are charging from home and you are worried about charging rates you feasibly could charge with either cable. If you do buy a Leaf with a 6.6kW charger, make sure both cables are included with the car (as they are £200+ to buy).

Finally, I should say I love the car. Its a joy to drive.


* from Battery Capacity Loss – Electric Vehicle Wiki
A question that is often asked is whether L2 charging (240 volts, 16 amps generally) is harmful to the battery. To put the question in perspective, you need to know that charging speed is measured by the C-rate, where 1 C is the current necessary to charge the battery in one hour. Since the Leaf with 3.3 kw charging takes a full charge in about 7 hours, the charging rate is C/7 (1/7 C). There is one study which measured the amount of capacity loss as a function of charging rate. It turned out that C/2 (about 12 kw for the Leaf) was the sweet spot and that slower or faster charging speeds had higher rates of capacity loss.
Conclusion: L2 charging at 3.3 kw (or 6.0 kw in some 2013 Leafs) is not expected to have a deleterious effect on the rate of battery capacity loss.
 

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Discussion Starter #5
I've just bought a 2nd hand leaf 2 weeks ago and went for the 6.6kW charger as a must.
Thanks all for your replies - most reassuring and confirms to me that I've made the right decision hopefully getting the 6.6 charger (car has a deposit paid and am viewing at the dealer this weekend).

If you don't mind me asking LeafSVB what did you pay for yours and what age / model /mileage is it ?

The car I'm hopefully getting is a 2016 Leaf 24 Tekna with just over 9k miles on it.

Thanks again all for taking the time to reply - assuming all goes ahead with the purchase i'll be frequenting the forum from now on (y)
 

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The car I'm hopefully getting is a 2016 Leaf 24 Tekna with just over 9k miles on it.

Thanks again all for taking the time to reply - assuming all goes ahead with the purchase i'll be frequenting the forum from now on (y)
The only concern I'd have is that the mileage is unusually low for the age - so it depends how the battery was treated. Being charged to 100% and left there isn't terribly good. This has occasionally been expounded upon in similar threads so won't drag it all out here - but generally batteries seem to age best with moderate use. Definitely don't pay a premium for a "low mileage" EV.

Hope it's a good-un. Best of luck.
 

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Discussion Starter #7
The only concern I'd have is that the mileage is unusually low for the age - so it depends how the battery was treated. Being charged to 100% and left there isn't terribly good. This has occasionally been expounded upon in similar threads so won't drag it all out here - but generally batteries seem to age best with moderate use. Definitely don't pay a premium for a "low mileage" EV.

Hope it's a good-un. Best of luck.
Was aware that the mileage was rather on the low side and of the issues you mention about batteries not liking being sat at 100% for ages. I have leaf spy and obd2 and will check SOH before purchase - i assume if there was any major concerns this would show it up ? I'm guessing if they tend to lose 3% (this seems to be forum general consensus) a year then i should be hoping to see it at 90% or better ? Is SoH a good enough indication or should i be looking at anything else on leaf spy - i seem to recall something about differentials in cells ?

Ive also budget crept from initially looking at a 2013 to now looking at a late 2016 to give it longer on the 8yr battery warranty.

I have it reserved with a deposit at £11750 which seems pretty good for a main dealer car with 6.6kw charger compared to any others i can find.

All subject to checking it out on Saturday though
 
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To be fair I took a bit of a chance myself - I got an October 2014 car in July 2017 that had been untaxed and clearly "floating about the dealer network" since October 2016. And it seems to have worked out OK. I've never bothered with Leafspy, but I'm mildly surprised to still have 12 bars (at least I did earlier today!) on the "SoH" display on the dash and haven't noticed any hugely obvious degradation yet. Since I've had it I generally use the charge timer to have it finish charging (and preheat) shortly before departing to work in the morning, with it set to 100% on Mondays and 80% every other day. I usually have the "long life mode" 80% charge limit set for any top-up charging during the day.
 
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