battery level

Go down to the magazine and count how many shells are left. Add the number in the ru lockers..

Hint. There are many types of battery. If yours is an unsealed lead-acid, you might use a battery hydrometer...

Submarine batteries, we used a 'height stick'. A glass/clear-plastic tube (acid resistent of course), marked off in 1/8 inches. Put end through a 'T' handle, so when put into the service cap hole, the cross-bar of the 'T' sat flush on the top of the cell. Put your finger over the top of the tube sticking out, and then pull the whole thing up out of the cell. Electrolyte is kept in the tube, much like a drining straw with your finger on the top of it. Measure the level in the 'straw' (the markings make this a snap), then put the end back in the service cap hole and release your finger to drain it back into the cell.

Lather, rinse, repeat....

Make your own, just use a tubing that is 1) clear so you can see the electrolyte inside it, 2) acid resistant. For a small battery, just put it down inside until it touches the plates, cover the end with your thumb/finger, retract and take the reading.

Some good sized 'stationary batteries' have cell jars that are clear for this very reason.

daestrom

Sorry I should have worded it better, what I meant by battery level was like how much left of charge there is. kinda like in mobile phones where the bars tell you how much battery is left to power the phone.

You do need to specify what sort of battery - eg nicad, alkaline, car battery, sealed lead acid, etc.

Some batteries have an output voltage that drops as the battery is discharged, so the voltage gives an indication of remaining charge. Some provide access to the liquid electrolyte and the density of that gives an indication of the remaining charge. Some burn a hole in the side of your laptop to show that they were, indeed, well-charged...