Is my battery faulty? Shuts off around 35%

[Hustler]

I have a new to me mid 09 macbook 2.13 c2d, 60gb ssd, 4gb ram. Its running 10.10.5 and the previous owner installed an aftermarket battery soon before selling it. He is unsure of its origins, but when I view the battery information in system report, it says the manufacturer is SMP. Cycle count is now 11, condition normal, max mAh 4766.
The issue I'm having with it is that from a full charge, it only gets down to around 35% ( I'm not sure the exact number, but I remember the times I've ran it down it gets to the low 40's and stays a few minutes longer) then shuts down. When I flip it over and push the battery indicator, its flashing on 1 dot. I can plug it in, let it charge for 20 minutes and it will be around 20-25% and I can unplug it and use it from that point down until 2% then it shuts down.
I thought that would be a battery calibration cycle, going from an actually indicated 0-100% then back down, but it still shuts down in the 35% area from a full charge after that.
I've tried resetting SMC with no positive results.

Anything else to check or that I can do?

 

[T5BRICK]

Sounds like a bad battery to me. I'd avoid 3rd party batteries.

 

[Hustler]

Sounds like a bad battery to me. I'd avoid 3rd party batteries.

Thats what I was afraid of.
I would consider the apple battery when replacing, but I've heard they don't make them anymore for the old a1181 MacBooks.

 

[Ovedius]

My better half started experiencing the same thing.

I've swapped her battery twice now.
Both times I bought a "genuine 100% original" battery on eBay.
The first replacement battery lasted about 6 months before it started to act funny, the second one has been working fine for 6 months now.
So I don't really know where you can be sure to get 100% genuine batteries.

But be sure to use the right tools though.
The screws that hold the battery down are propriatery Apple screws and can easily be broken with flat or phillips screwdrivers.

 

[Hustler]

My better half started experiencing the same thing.

I've swapped her battery twice now.
Both times I bought a "genuine 100% original" battery on eBay.
The first replacement battery lasted about 6 months before it started to act funny, the second one has been working fine for 6 months now.
So I don't really know where you can be sure to get 100% genuine batteries.

But be sure to use the right tools though.
The screws that hold the battery down are propriatery Apple screws and can easily be broken with flat or phillips screwdrivers.

I've read some good reviews about Anker brand batteries on Amazon so I'll probably go with them when I finally do.

And it would be tough to get my battery wrong, on the a1181 white MacBooks the special tool needed is a penny, lol.

 

[Ovedius]

I've read some good reviews about Anker brand batteries on Amazon so I'll probably go with them when I finally do.

And it would be tough to get my battery wrong, on the a1181 white MacBooks the special tool needed is a penny, lol.

Oh right! Those machines had really easily swappable batteries.
I forgot!
Unlike the MacBook Pros where you had to remove the bottom and unscrew the battery.
Well in that case, no worries.