e-Pedal and Battery Life

I don't know much about batteries but I know that it's not very good to plug and unplug your electronics with batteries without giving them a 20 -> 80% charge and somethings to 100% to help 'rest the cells' - this is what I read so far. But the e-pedal is constantly providing a small amount of charge to the battery and I was wondering if this is harmful to the battery life?

I can't give the scientific answer like the folks who get into gids and pack balancing- but I've had my leaf for almost 5 years and have driven almost exclusively in B mode and at almost 50k miles my battery has 10 bars SoH. Generally if there's a full or mostly full charge it doesn't do regeneration or does it very minimally.

Not "rest the cells" but "balance the cells" in order to make sure that they are all at about the same voltage.

e-Pedal doesn't hurt the battery's cells because it is prevented from overcharging them. I'm not sure, but I assume that using e-Pedal with a fully charged main battery will result in reduced regeneration until the state of charge of the battery drops a bit.

pr0lab said:

I don't know much about batteries but I know that it's not very good to plug and unplug your electronics with batteries without giving them a 20 -> 80% charge and somethings to 100% to help 'rest the cells' - this is what I read so far. But the e-pedal is constantly providing a small amount of charge to the battery and I was wondering if this is harmful to the battery life?

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In the grand scheme of things, it's not harmful. Does it affect cycle life of the battery? In a technical sense it does, but the effect is so small and the conditions needed for it to become harmful are so rare, it's not something to worry about it. Batteries of this size are affected much more by heat and the stress of over-discharging or leaving at a high state of charge for long periods more than anything when it comes to a measurable effect.

Thank you all!

What about charging? Do I need to worry about charging it until 80% or should I just let it go to 100%, assuming Leaf is set to stop below the "full charge" level?

On the flip level, when should I start charging? should I, in general, try not to go below 20%?

Try to stop at 80-90% in Winter, 60-70% in Summer, unless you actually need the full range. Try to keep it above 20-25% year round, but it's ok to go down to 10% if you plug in immediately afterward.

LeftieBiker said:

Try to stop at 80-90% in Winter, 60-70% in Summer, unless you actually need the full range. Try to keep it above 20-25% year round, but it's ok to go down to 10% if you plug in immediately afterward.

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Thank you. this is useful info!

pr0lab said:

LeftieBiker said:

Try to stop at 80-90% in Winter, 60-70% in Summer, unless you actually need the full range. Try to keep it above 20-25% year round, but it's ok to go down to 10% if you plug in immediately afterward.

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Thank you. this is useful info!

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You're welcome. The other Big ones are:

* Avoid leaving the car at 100% charge for long periods (more than a couple of hours in Summer, more than a day in Winter), especially in hot weather. If you need a full charge for a trip, time the charge to end shortly before you leave.

* Avoid DC Fast Charging if the battery shows more than 6 temp bars. As with most of these suggestions, this is especially true in warmer weather, and especially true in Hot (80+F) weather.

thanks again! amazing info. wrote all of this down for myself to use as a reference.

Another question as it relates to battery life that has been the "useful battery life cycles". For example, Apple publishes that iPhone should be at 80% capacity after 500 charges. Is that derived from the actuals charges that the battery takes or the health of this battery during this milestone?
Asked differently, is it better to charge 10-90% vs. 20%-80% to reduce the total number of individual charging cycles?

pr0lab said:

Another question as it relates to battery life that has been the "useful battery life cycles". For example, Apple publishes that iPhone should be at 80% capacity after 500 charges. Is that derived from the actuals charges that the battery takes or the health of this battery during this milestone?
Asked differently, is it better to charge 10-90% vs. 20%-80% to reduce the total number of individual charging cycles?

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That would be more of an Apple question about what they mean by that statement. Usually charge cycles mean start with full charge, full discharge, then recharge battery, repeat process. So, in a lab, the battery might go through it 500 times. In real life, people may only half-discharge their phone, then charge back up to full. So that would technically be "half" a cycle. If you discharge your phone to 50% and then charge to 60% and then discharge to 50% again, that doesn't count as a full cycle, but a small fraction of one. You can see how the math can get confusing from that point onward.

thanks. This make sense. Just wanted to understand if batteries have this understanding of cycles.

I am a new Leaf owner and I find that I never need the 100% charge so far. Is it ok to only charge up to 80% all the time? How often should I go to 100% on purpose for cell balancing?

80% all the time is great. Li batteries have no memory effects and they tend to last longest when operated in the middle of their range. You can go to 100% also but it's best not to let the car sit in that state for a long time, so when charging to 100% be sure to drive the car soon afterwards to bring the SOC back down.

The BMS (Battery Management System or the computer(s) that control the battery) will get better data points to calculate the capacity of the battery, etc when the battery is charged to 100% but otherwise, there is no real benefit to charging to 100% that I know of.

Charging to 100% probably also allows extra time for balancing since the charging current is ramped down towards 0 but the balancing continues so it may help with keeping the cells balanced. How much that helps or how unbalanced the cells will be if you never reach 100% SOC varies from car to car. At this point it's really getting into some minute differences so I wouldn't sweat it overall unless you like to geek out on this stuff. And if you do, you should get LeafSpyPro so you can monitor your battery stats to the 0.1% level. :mrgreen: