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Apple Computing Products:
macOS - Notebook Hardware
Macbook pro, how to treat the battery ?
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<blockquote data-quote="MunkeyQ" data-source="post: 1235528" data-attributes="member: 129637"><p>Nope. This is because when the battery is charged, the management circuit cuts off power to it completely and since over time, the battery discharges by itself so the computer applies what's called a "topping charge" when it drops below the low fully-charged threshold. Li-ions can't be trickle charged.</p><p></p><p>So once the battery hits 100%, the computer stops charging it. When it drops by itself through self-discharge to 98% (this is just an example), it will charge once again until 100%. IBM Thinkpads have a handy utility which lets you view battery voltage and charge current; it shows this happening very nicely. Don't think there's one for Apple hardware though.</p><p></p><p> </p><p></p><p>No laptops do this. It would be incredibly bad design as the computer would be unable to run at full speed with a battery that's reached the end of its useful life. I'm afraid that's a myth - no Li-ion management chips will do this.</p><p></p><p></p><p><em>Extra note: self-discharge is one reason why the battery's voltage drops after a full charge, but it's also because of the surface charge effect, present in an extent in lead-acid batteries too. Macbooks fast-charge (high current) the battery up until 80%, and then slowly fill the rest for proper end-of-charge termination detection. However, when fast-charged, the chemical reaction happens slightly faster at the edges of the plates - when left to sit for a 10 mins or so, the reaction spreads to the centre, decreasing nominal voltage.</em></p><p><em></em></p><p><em>It's why if you crank your car until the battery no longer turns the starter motor and then try again in half an hour, it seems to regain a bit of life.</em></p><p></p><p>Hope this helps!</p></blockquote><p></p>
[QUOTE="MunkeyQ, post: 1235528, member: 129637"] Nope. This is because when the battery is charged, the management circuit cuts off power to it completely and since over time, the battery discharges by itself so the computer applies what's called a "topping charge" when it drops below the low fully-charged threshold. Li-ions can't be trickle charged. So once the battery hits 100%, the computer stops charging it. When it drops by itself through self-discharge to 98% (this is just an example), it will charge once again until 100%. IBM Thinkpads have a handy utility which lets you view battery voltage and charge current; it shows this happening very nicely. Don't think there's one for Apple hardware though. No laptops do this. It would be incredibly bad design as the computer would be unable to run at full speed with a battery that's reached the end of its useful life. I'm afraid that's a myth - no Li-ion management chips will do this. [i]Extra note: self-discharge is one reason why the battery's voltage drops after a full charge, but it's also because of the surface charge effect, present in an extent in lead-acid batteries too. Macbooks fast-charge (high current) the battery up until 80%, and then slowly fill the rest for proper end-of-charge termination detection. However, when fast-charged, the chemical reaction happens slightly faster at the edges of the plates - when left to sit for a 10 mins or so, the reaction spreads to the centre, decreasing nominal voltage. It's why if you crank your car until the battery no longer turns the starter motor and then try again in half an hour, it seems to regain a bit of life.[/i] Hope this helps! [/QUOTE]
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Apple Computing Products:
macOS - Notebook Hardware
Macbook pro, how to treat the battery ?
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