Re: Question on lithium ion batteries.

On 24/01/15 13:41, James Linder wrote:
>> On 24 Jan 2015, at 9:00 am, [email protected] wrote:
>>
>> So, having absorbed, from my friends,  the dangers of partially recharging
>> a  lithium-ion battery due to “memory”, I read the insert that came with
>> the new laptop battery:  –
>>
>> “Recharging a partially charged lithium-ion does not cause harm because
>> there is no memory. Short battery life is mainly caused by heat rather than
>> charge/discharge patterns.”
> Terry Pratchett: He does know Big Words after all he is a dealer …
>
> Battery Technology is VERY complex, so either you become a guru or you believe the manufacturer.
>
> lithium-ion is complex enough that I cannot believe that a manufacturer would make a charger that does not do the right thing. (lithium-ion-phosphate may NEVER be flattened, so even more complex)
Battery manufacturers primarily compete on capacity on the date of purchase.
If the battery lasts 18 months instead of 2 years most of the time the 
short lived cell isn't going to be held against the manufacturer.

Discharging any lithium chemistry cell to 0 volts will pretty much 
destroy it.


>
> The only severe rule for mortals is to never charge A sort batteries with a B sort charger the consequences are fire and explosion.
>
> I opine that you may use the laptop permenantly 'on charge’ yet I have seen a disportionate number of dead laptop
> batteries contradicting what I say above.
>
> General Rule #1: Every time you flattern a battery you use up a percentage of it’s life.
>
> The ideal charger would keep the batteries at 99% charged allowing you to always charge (not 100% because the 100% level is temperature dependant and you don’t want to go to 101% because the day warmed or cooled)
> So if you have bought a system with a lessor charger you will buy batteries, the more you play the better the battery life, but like death and taxes dead battries.
>
> James
I have seen some phones and laptops (very rare) that won't charge if the 
battery is above 90something %, those ones you could leave on charge 
without damaging them.
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