The Leaning Tower of the planet Crimson is an accessible location which holds the Battery on its top floor.
To get to the leaning tower, follow the path on Crimson and take the first left in the first intersection. Then, take the left fork at the second intersection and there will be a gate. The gate is unlocked by cutting it open with the Bolt Cutters that are located near the Crimson Rover Shop (directions on Crimson Rover Shop page). Then, follow the tunnel that leads to the Leaning Tower.
The Three Mazes
To get the Battery, you need to go through three mazes, each one harder than the last. Each maze leads from the previous ladder to the next ladder, as the tower has 3 maze floors. If you have troubles navigating on your own, you could look at the guide below. After you completed all the mazes, you will be greeted by the Battery which you could take and use to unlock the Forgotten Quarry.
Red means start and Green means the end.