[ltp] Battery croaked

[Dmitry E. Mikhailov]

> Do you have any idea about the differences between *original* and
> *second-choice* batteries (as I see in ebay) ? I never test
> second-choice battery.
First of all, new original battery should look exactly like your current 
original battery. No scratches on the plastic. No badly glued labels. But 
counterfeit batteries are like counterfeit money. Sometimes it's hard to say 
if it's a fake. You can try to distinguish it by price. Usually an original 
laptop battery costs about $100 or more. If they sell it for $30, don't 
expect it to be that good.


> How many time a battery can be warranted :
> I establish more than 2 years for an original battery ?
The Li-ion battery generally loses 50% every two years. But if you own a 
thinkpad, you can deal with it. Li-ion batteries don't like to be fully 
discharged and to be fully charged. Under these circumstances they degrade 
faster. On thinkpads an embedded controller can control the charge, not just 
simply push the battery to it's 100%. I have a two-year-old X41 and I got 
that:

root@ibm scriptlets.d]# cd /sys/devices/platform/smapi/BAT0
[root@ibm BAT0]# cat last_full_capacity
24020
[root@ibm BAT0]# cat design_capacity
27360

I lost 12% of the capacity in two years. That's because of:

[root@ibm BAT0]# cat start_charge_thresh
40
[root@ibm BAT0]# cat stop_charge_thresh
70

So the battery is being charged only if it's at 40% or less, and the charge 
stops at 70%. 

> But I ignore the age a second-choice battery can last.
Less than original. Much less. As for (my) cell phones, el-cheapo batteries 
die in about 6-8 months. Too bad, but I don't have any way to get an original 
one.

> These second choice battery are sold with a right capacity.
> Is it the real capacity or not ? What is this capacity 6 month after ?
Can't say much for laptop batteries, but AFAIK it's just the same stuff as 
cellphone batteries. So:
The original battery for my SonyEricsson P900 smartphone is 1260mAH
The spares were rated the same. But after they die, I remove the plastic 
shielding to get to the cell itself. Then google for the code printed on a 
cell. I got 3 batteries. They are 850mAH, 900mAH and an unidentified one. So 
they are initially worse than an original battery. The production quality 
make them degrade faster so the capacity drops further. As I can say, you get 
the half of the rated non-original battery capaticy. I wish I could by an 
original, but can't find one.

And yes, most of the batteries (even genuine one) are made in asia but there 
are so much differences between Japan and China :-)