Robot and the battery

[Emerald]

So i'm trying to find a way to give the battery back to the first robot you meet in book 2 and promise to help, issue is i think i know where the last 4th battery is and it's in a locked box in the battery powered lockers, the problem is that i can't find a way to open it as i do not know what item is required and none of the ones i have are up to the task. (you cant lockpick it or break it open with the original tools).

[Futility]

It's not there. You will have an opportunity to obtain a spare battery later.

[Emerald]

Where exactly, i have looked everywhere and could only find 3 batteries

[Oleg Sergeev]

Originally posted by Emerald:

Where exactly, i have looked everywhere and could only find 3 batteries

This option will appear in a Conveyor Belt room later on.

[razzazzika]

Hey. Late to the party. I decided to brute force the conveyor belt puzzle on my second playtrhough hoping I could find more apples like the first box you get, and found the spare battery! (If you care 4 months later) it is A7-1-5!

(I know they had a small part, but I loved Modi, reminded me of Baymax)

[razzazzika]

Oh, and for anyone from the future, A7-2-1 has some stale bread and an apple, if you like me are looking for rations.

[gpedro178]

I don't now if the battery thing at the conveyor belt is random but I found the spare one using the first letter on the selectable list, the second character was "1" and the third one I think was also "1".
I forgot to try using it on the starting robot...