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Maybe once or twice a week at most, if so very rarely from less than 50/60%.

My charging is entirely on the public network - just driving around town, I generally only need one charge a week, and for longer distance stuff it's a mix of destination and rapid charging.

Ahh i use at least 50% on an almost daily basis, sometimes more, thats why my milage is climbing so much, and as with you, almost entirely public other than some top ups at my partners on the drive.
More so when there are no freevends around lol
 

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Does anyone here use the charge timer deliberately as a means of reducing battery degradation ? I'm looking at getting a 30kWh Leaf and it's a bit disappointing that the 80% charge option was removed in the Gen2...as I could easily do my commute from 80% SoC down to about 40% SoC in a 30kWh model....(maybe 30% in winter)

However it occurs to me that the charge timer could be used as a poor mans charge limiter by limiting the amount of time the battery spends sitting at 100% and as degradation at a high SoC is cumulative with time, reducing that time reduces degradation. So for example set the charge end timer to 6am and preheat timer to 7am. (I leave the house about 7:15)

Assuming the car had a 6kW charger my 35 mile daily commute would require approx 2 hours to recharge. If I just plugged it in when I get home at 6pm and started charging immediately it would be charged by 8pm or 9pm at the most including cell balancing and then sitting around 11 hours at full charge before next use. Not good.

However if the charge timer brought it on at say 3am to meet the 6am deadline it would only spend an hour or two near full charge before being driven again, reducing the time spent at full charge per day from 11 hours down to around 2 hours. This must surely be beneficial.

There are two potential temperature related benefits as well. In the summer when the battery may be warm/hot after the journey home charging immediately (especially at 6kW) will push the cell temperatures up a further several degrees - probably at last 6 degrees on a 6kWh charger. However if the timer doesn't start charging until 3am that gives nearly 9 hours for the cells to cool down before charging - in that time the cell temperatures should drop quite a bit, and while the charging process will warm the cells up by approx the same number of degrees (same power dissipation) the starting point will be lower so the peak temperatures reached will be lower, and this is good in the summer.

Meanwhile in the winter the temperature increase from charging can be beneficial to warm the battery up before leaving in the morning, so in winter it's also best to leave the charging until the last moment to maximise the cell temperatures at departure time (poor mans battery heater) rather than charging early in the previous evening and then having the cells cool right down again on a frosty night.

Of course its good for the local grid supply to charge in the early hours of the morning if possible as well, and it makes me feel guilty plugging in my Ion at 6pm every night at peak time (albeit at 3kW) however I do this as neither the car or EVSE has a timer, and there is too much risk of forgetting to plug it in manually later in the evening, (leaving me with not enough charge to get to work let alone do a return trip) however if I had a charge timer in the car I would gladly use it to delay my charging past peak hours.

It's annoying that there is no battery thermal management and no 80% charge limit option, (there's no excuse for the latter when the feature was there in the Gen1) but in the absence of those it seems wise to make use of the charge timer as described above.
I use timer for 3 hours in middle of the night no specific reason for that I don't get cheap rate. I have the 3.3 OBC so I get about 30% extra.
When I need a full charge I set the timer with a finish time only, this ensures the battery has just reached 100% when I am leaving. In your case you could set the finish time an hour or so after you need to leave so will not be at 100%. A bit of trial and error will get the result your looking for.
 

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Why worry about it unless your getting a high mileage vehicle?
As long as its a 30kwh and under 100,000Miles or 8Years old, your covered to 75% capacity :)
And lets be honest, when nissan replace a pack they will be a Remanufactured unit but they are unlikely to be below 95% SoH, more likely as close to 100% as they can to avoid issues and there has been the talk of the software locked 40kwh packs being fitted for longer life as well.
 

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Why worry about it unless your getting a high mileage vehicle?
As long as its a 30kwh and under 100,000Miles or 8Years old, your covered to 75% capacity :)
And lets be honest, when nissan replace a pack they will be a Remanufactured unit but they are unlikely to be below 95% SoH, more likely as close to 100% as they can to avoid issues and there has been the talk of the software locked 40kwh packs being fitted for longer life as well.
Why worry about it ? Because I would be buying a low mileage vehicle (10-30k) and putting a lot of yearly mileage on it (around 15k/year) and hoping to keep it for at least 4 years. And actually buying it, not PCP'ing it, and wanting to have a good battery SoH remaining by the time I sell it, and a good usable range for the duration of my ownership.

Since I would own it, of course I'm going to do everything I can to treat the battery well and minimise degradation. And if using the charge timer to delay charging can help with that, it would be lazy of me not to make use of it.

A battery warranty to 75% SoH is all very well, but by then it would have the same range as a Leaf 24 - why would I want a Leaf 30 that had the same range as a 24 due to battery degradation ? Seems a bit pointless if I can try to minimise degradation.
 

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I use timer for 3 hours in middle of the night no specific reason for that I don't get cheap rate. I have the 3.3 OBC so I get about 30% extra.
When I need a full charge I set the timer with a finish time only, this ensures the battery has just reached 100% when I am leaving. In your case you could set the finish time an hour or so after you need to leave so will not be at 100%. A bit of trial and error will get the result your looking for.
I like the hack of setting the charge end timer an hour or so after the leaving time, the last hour of charging will be at a lower rate with balancing so should be fairly predictable. The only problem I forsee is a clash with the pre-heat timer, which is why my original idea was to have the charge end timer set an hour before the preheat timer. I see you can set a priority between the two so I might have to experiment with that to find what works best. And of course it would depend on whether I get a 3.3 or 6.6kW charger. I'm hoping to find one with a 6.6kW charger but not having it is not a deal breaker.
 

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42k miles on public charging. Am I an expert yet?
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Just bear in mind that if you never let the car charge to 100%, it'll never have a chance to balance the pack properly, and the balancing time can be highly variable. The car isn't very good at predicting balancing time...also balancing seems to stop if the preheating is started before balancing is finished, in my experience.
 

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Yep I'm aware of these factors. I would still charge it up to 100% now and then, the point is just to avoid doing it every day, or have it charge to 100% soon before it was going to be driven again.

If the battery is healthy it shouldn't need constant balancing - keep in mind that most EV's don't do any cell balancing when rapid charging, (as the charge rate is too high relative to the discharge rate of the cell bleed resistors) so a car that is only ever rapid charged and rarely level 2 charged would be in the same situation.
 

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Why worry about it ? Because I would be buying a low mileage vehicle (10-30k) and putting a lot of yearly mileage on it (around 15k/year) and hoping to keep it for at least 4 years. And actually buying it, not PCP'ing it, and wanting to have a good battery SoH remaining by the time I sell it, and a good usable range for the duration of my ownership.

Since I would own it, of course I'm going to do everything I can to treat the battery well and minimise degradation. And if using the charge timer to delay charging can help with that, it would be lazy of me not to make use of it.

A battery warranty to 75% SoH is all very well, but by then it would have the same range as a Leaf 24 - why would I want a Leaf 30 that had the same range as a 24 due to battery degradation ? Seems a bit pointless if I can try to minimise degradation.
Because by that point the battery would then go in for replacement and youd have a much more valuable leaf to sell on?

FYI I owned my last leaf and this one and put about 25k on every 9 months without issue. Degredation seems more age based i have found from my leafspy shots of my current and last ones.
 

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I like the hack of setting the charge end timer an hour or so after the leaving time, the last hour of charging will be at a lower rate with balancing so should be fairly predictable. The only problem I forsee is a clash with the pre-heat timer, which is why my original idea was to have the charge end timer set an hour before the preheat timer. I see you can set a priority between the two so I might have to experiment with that to find what works best. And of course it would depend on whether I get a 3.3 or 6.6kW charger. I'm hoping to find one with a 6.6kW charger but not having it is not a deal breaker.
Bare in mind that if you get the 3.3kw vehicles that when they preheat they cant pull enough juice thru the charge lead to stay at an even level of charge in the colder days.
The same as the 6.6kw like mine but on a granny lead or 3kw chargepoint :(
 

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Because by that point the battery would then go in for replacement and youd have a much more valuable leaf to sell on?

FYI I owned my last leaf and this one and put about 25k on every 9 months without issue. Degredation seems more age based i have found from my leafspy shots of my current and last ones.

SoH variations based on my Leafspy logs over the last 15 months

BTW there's a dedicated thread for Battery health.. why discuss battery health in BMS update thread ?
 
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