A1398 2012 shutdown at 40% battery discharged

[Yordanov]

When this A1398 get low to 40% will suspend or shutdown. Battery problem? SMC problem? Something to check first?

 

[JohnB8812]

Resoldered/reflowed U8900?

 

[dukefawks]

Battery. So many of these batteries are crap. Don't bother getting a "new" one as the Chinese just take a crap battery and reset the cycle count and charge capacity. Usually the shutting down at 20-30% are the Chinese ones because the charge capacity was reset.

 

[Yordanov]

With any program is possible to check that? Or they clear all parameters?

 

[dukefawks]

Nope, this is a battery issue and I bet it is already one of those chinese batteries. See if it is stuck in the case really good, the chinese ones usually flop around as the tape is crap.

 

[Yordanov]

Yes, it is chines one. I bought it as "new"

 

[dukefawks]

Garbage battery, good luck finding something that works......hopeless.

 

[Yordanov]

I recived another battery that work 5 hours from 100 to 0% and it shotdown at 0%. Not before.
So can I considere this battery is good? Should I try anything else?

 

[dukefawks]

It should not shut down but go to sleep. But this is better than nothing so just leave it. These batteries are hopeless.

 

[Yordanov]

If chines recicly batteries then they can take batteries wih 100 cycles and reset them and they can take ones with 800 cycles. With coconut it it impossible to check any parameter and see if battery will be good? If this battery had 100 cycles it will be like new. But how to know that?

 

[dukefawks]

Chinese know exactly what batteries they are selling and they are NOT giving the good ones to you.

We can only wait until the supply of pulled garbage batteries dries up and someone HAS to make something new. Just don't have many hopes.

I got 9 batteries today and the first one reported the fake 8700mAh capacity. It then shut down at 18% charge and the charge capacity dropped to 7300mAH. HOPELESS GARBAGE everywhere....just forget about replacing batteries that still work but just have a bit lower capacity.

 

[Yordanov]

I will try new one from another supplier and will test this week.

 

[dukefawks]

Good luck with that. I'm done with these.

 

[Yordanov]

Will try an tell you. It is provider that tells me it is 100% new and hight quality. What problems can I except? So I can test it well? After that will inform.

 

[dukefawks]

Of course they will say it is 100% new. These sellers have no idea what they are really selling.

Just run the battery till empty and watch it shut down at 20% or so. A few really deep discharger/recharge cycles may bring the full charge capacity closer to reality and make the shut down issue less of a problem.

Just look at the charge capacity and voltage. I have batteries here that are reporting to have 2000mAh and the voltage is at 9.5V, total bull shit of course. Charge capacity should be 0mAh at around 10.5V, that is in the ball park of normal.

 

[Yordanov]

If coconut tells 90% could be bad battery also? Did you have such case? Or 90% will be good in most cases?

 

[dukefawks]

You cannot tell as the Full Charge Capacity has been reset by your Chinese friends. Run it down till empty and see when it shuts down

 

[Yordanov]

Well coocnut says design capacity that chines reset and real capacity. Real capacity is measured in the moment, right?

 

[dukefawks]

The whole thing is messed up because no calibration cycles were done after the reset. If they would do that it the capacity would fall back to probably 70%. Also the cells need to do an impedance balancing, there is too much to this to explain here.