There has been a lot said about the battery performance issues in the Nokia Lumia 800. But there was no official word on the issue till date. Though now Nokia has come out in the open and accepted the fact that there are battery issues with the Nokia Lumia 800.
As per the statement issued by Nokia there is nothing wrong in the battery provided with the device, but the software which is causing the underutilization of the battery as a result the batteries die down a lot sooner than they should.
As per Nokia, this bug is not present on the latest batch of Lumia’s. So in order to confirm if your handset is affected by the bug or not, you need to dial ##634# to open up the diagnostics tool and then select ‘battery status’ after accepting the T&C. And now if your battery capacity shows less than 1000mAh you have the battery issue if not then you are fine.
Nokia has promised an update for the same early next month which will fix the software bug and thus the full 1400mAh battery in the device will be utilized. In case you do not want to wait for the software update, Nokia also gives you the option to exchange the device at the Nokia store.
Remember that this is a different issue than the charging one wherein the device once out of battery refuses to even acknowledge charging and start up even after almost half an hour of charging. A small maintenance release for the same is also expected early next month.