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Just trying to settle an argument. How often should i let the battery run down to 0?

Asked: May 21 2016 | 7:55 pm EDT 2947 Views 12 Answers View Best Answer

I have a 17" 2010 MacBook Pro, with a Lithium-Polymer battery.


Best Answer

51,632
May 21 2016 | 8:13 pm EDT Just_Me_D

Charge your Apple lithium-ion battery whenever you want. Theres no need to let it discharge 100% before recharging. Apple lithium-ion batteries work in charge cycles. You complete one charge cycle when youve used (discharged) an amount that equals 100% of your batterys capacity but not necessarily all from one charge. For instance, you might use 75% of your batterys capacity one day, then recharge it fully overnight. If you use 25% the next day, you will have discharged a total of 100%, and the two days will add up to one charge cycle. It could take several days to complete a cycle. The capacity of any type of battery will diminish after a certain amount of recharging. With lithium-ion batteries, the capacity diminishes slightly with each complete charge cycle. Apple lithium-ion batteries are designed to hold at least 80% of their original capacity for a high number of charge cycles, which varies depending on the product.

Source: http://www.apple.com/batteries/why-l...80&subId2=vbim

https://support.apple.com/en-us/HT204054

More Answers

167
May 21 2016 | 10:41 pm EDT rdmartin1

IIRC it says once per month.
2,358
May 21 2016 | 10:58 pm EDT grunt0300

Thanks guys. My daughter had a Mac from 2007, and she always left it charging. The battery exploded inside the machine, and the repairman told her to let it run down to 0, and then charge it every day.
5,469
May 22 2016 | 12:06 am EDT mumfoau

I NEVER let anything run down to 0 or even close to it
842
May 22 2016 | 8:47 pm EDT Fit24

I never completely discharge my battery.
290
May 23 2016 | 3:42 pm EDT Branta

Never take a lithium based battery down to zero unless your life depends on using those last few electrons. Under no circumstances try to trick the battery into charging above nominal 100% unless you like making work for firefighters and paramedics. Ideally keep it above about 30% if possible. Here's a clue... most new rechargeable lithium batteries are charged to 40-50% for best shelf life in storage before delivery to the user.
42,948
May 23 2016 | 3:54 pm EDT Ledsteplin

A lot of people say different things about the lithium ion batteries. It makes for a lot of confusion.
290
May 24 2016 | 1:28 pm EDT Branta

A lot of people say different things about the lithium ion batteries. It makes for a lot of confusion.
Whatever they say different there are two things guaranteed to kill a lithium battery:
1: Deep discharge to silly low voltage. Most phones have protection circuits to shut down before the battery is irreversibly damaged.
2. Overcharging. This can cause thermal runaway and a spectacular fire or exploding phone.

It seems to be a widely held opinion and it certainly aligns with my experience that deep discharge (to shutdown level) usually has a disproportionate hit on battery life. You won't see it fron one or two flat battery events, but if it is a regular occurrence the battery capacity will degrade faster than by keeping it topped up when possible. I frequently charge in the car so my batteries are usually well charged, and I have several batteries 3-4 years old still going well.
2,899
May 24 2016 | 1:44 pm EDT Honey Beagle

I have a weight scale to check ones weight. I purchased this scale in the 1980s. Battery has never been changed, no way to charge tge battery. This is a lithium battery. Called litheum electronic scale.
13,320
May 24 2016 | 7:33 pm EDT Rob Phillips

I have a weight scale to check ones weight. I purchased this scale in the 1980s. Battery has never been changed, no way to charge tge battery. This is a lithium battery. Called litheum electronic scale.
What version of iOS is it running?
2,899
May 24 2016 | 10:20 pm EDT Honey Beagle

I have no idea. Does not have that on the scale anywhere. Just press on the scale to get all zeros. Then stand on scale and get ones weight.