.. The second thing the battery needs

The object itself doesn't matter, just as long as it's made of copper.

It could even be something random, like a cooking utensil. Wink, wink.

Item locations have been pretty devoid of logic thus far, but the cooking utensil is exactly where you'd expect it to be.

Visit the kitchen - you'll find a copper ladle next to a big pot.

If the kitchen's locked off, follow these hints.

Next up - something made of zinc.