Does the MacBook Pro 15'' 8,2 Early 2011 accept both A1321 and A1382 batteries? I have a MacBook Pro 15'' A1286, model 8,2 Early 2011 (with i7 @ 2,3 GHz).

Inside is a A1382 battery telling that it must be replaced.

I have in stock a A1321 battery which is in good condition.

The two batteries use same voltage, have same shape and the connector is at the same location. Furthermore, the both connectors plug without problem into the female socket on the motherboard.

The majority of vendors MacBook batteries commercialize:


the A1321 for 2009-2010 MacBook Pro
the A1382 for late-2011 and later versions of the MacBook Pro


For above MacBook models, the two batteries are uncompatile.
In this thread, Jozef Vaclavik explains that the order of pins is different, although the connector is same. With proper equipment and knowledge, the pins could be inverted.

But what about the early 2011  MacBook Pro 15''?
It seem that most vendors commercialize the A1382 battery for it, but some other commercialize the A1321.

I would be surprised if a corporation like Apple had designed a model that could possibly present a risk of battery explosion in case of a improper battery swap.

So, could the early-2011 MacBook Pro 15'' be a transition model and natively accept both batteries thanks to a voltage inverter on the board?

Is anyone using a A1321 battery inside the early 2011 MacBook Pro 15'' 8,2?
Regarding your statement that:


  But what about the early 2011 MacBook Pro 15" ? It seem that most vendors commercialize the A1382 battery for it, but some other commercialize the A1321.


I haven't come across this scenario, so can't comment on your source for this. 

However, officially the A1382 battery is compatible with all of the 15.4" A1286 models of MacBook Pro from the Early 2011 models up until the Mid-2012 models.

And, officially, the A1321 battery is compatible with all of the 15.4" A1286 models of MacBook Pro from the Mid 2009 models up until the Early 2010 models. They are not officially compatible with the Early 2011 models.

Were you to use an A1321 battery in the Early 2011 models you would be doing so at your own risk.