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Battery advice apples to other devices?

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Battery advice applies to other devices?

So after reading this forum, it seems pretty clear that I shouldn't regularly charge my tesla to 100% because it isn't good for the pack.

Does this hold true for my laptop, apple watch, and my iphone as well?
Should I be charging up to 90% on those as well?

I always thought charging them up to 100% overnight was a good thing. I'm curious to hear what this forum says because it sounds like we have a lot of folks on here that are knowledgeable on batteries.
 
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Thinkpad laptops had an intelligent BMS that allowed the user to set the SoC level when charging stops and the level when it resumes. I used to have them at 96% and 90% respectively. The problem with the mobile devices is that the battery is always undersized for portability and cost reasons.

I have yet to charge my 3-month old 70D to 100%. The limit is still set at 90% from the factory, which in the warm weather is giving me rated 215 miles, more than plenty.
 
Lead acids are different, as are NiCd and NiMH. This only applies to Lithiums.

Since getting the Tesla and learning about Li batteries, I generally pull my cell phone out of the wall at 80%, if I happen to be around. My Norelco electric shaver charges very quickly, so I typically charge it in the morning before shaving, so it doesn't sit at 100% - like a range charge :smile:
 
My daughter’s netbook had a battery saver function that would let you set the max charge to 80% to help the life of it. In general, as others have mentioned, the reason this isn’t common on laptops, cell phones, and such is kind of a cost and convenience tradeoff. People usually want the most energy they can have while they are using it each day, so they want it to start at 100%. And even if that does damage to battery, and it needs replacing in 2 or 3 years, there are one of two results at that point: (1) People frequently are buying a newer better device about that time, so they don’t care about the shortened battery life in the old device. OR (2) They may buy a newer battery, which is about $10-$15 for a phone or $40 or so for a laptop, which isn’t any big deal for a few years of use. With the much more expensive battery packs in cars, and the longer lifetime they usually have, it matters quite a lot more to try to make them last a lot longer.

And @bmc, good grief—could you please change the thread title to “applies”, rather than “apples”?
 
I've wondered about this. What about lead-acids? A UPS that backs my desktop sits fully charged all the time but I thought it wasn't a big deal given the different chemistry.
Lead-acid needs to be kept at 100% for optimal life. Less and insoluble lead sulfate forms on the plates, killing it. Lower depth-of-discharge, and recharge ASAP to 100% is the key to PbA longevity.
 
Heat is probably one the major issues for cell phones. Too often they are left in hot places. Yes charging to 100% is not good, but it's far less of an issue for cell phones as long as you disconnect the charger once it's full. Letting the battery go down to zero to the point where the device shuts off is also bad. But frankly, cell phone batteries are not expensive to replace, so don't worry too much.

Many laptops have a battery care feature. My Sony has three options. 100%, 80% or 50%.
 
With enough apples you could charge a device or two. I recommend Granny Smith, they have a higher acidity than most apples.

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So after reading this forum, it seems pretty clear that I shouldn't regularly charge my tesla to 100% because it isn't good for the pack.

Does this hold true for my laptop, apple watch, and my iphone as well?
Should I be charging up to 90% on those as well?

I always thought charging them up to 100% overnight was a good thing. I'm curious to hear what this forum says because it sounds like we have a lot of folks on here that are knowledgeable on batteries.

You don't really know whether you are charging your laptop or smart phone battery to 100% unless you find out from the manufacturer how much of a cushion they build into their chargers. They may have their chargers set up to stop at 90% of cell charge capacity to preserve battery life, but report to the user 100% because it's easier than trying to explain why they go only 90%.
 
You don't really know whether you are charging your laptop or smart phone battery to 100% unless you find out from the manufacturer how much of a cushion they build into their chargers. They may have their chargers set up to stop at 90% of cell charge capacity to preserve battery life, but report to the user 100% because it's easier than trying to explain why they go only 90%.
It would surprise me if they didn't charge to 100%. One of the numbers often quoted with laptops and how long it will run on a charge. Do you think a mfr would lower that number so the battery has a longer lifespan?