- 1). Get as many LR41 button cells as you need to power your device, so if you need 9 volts, get six LR41. They are widely available from electrical, camera and hobby shops.
- 2). Place the LR41 button cell batteries on a table in a row. Cut two strips of AWG18 gauge wire using a knife. Cut the strips the length you need to reach between the button cells and the device you intend to power.
- 3). Remove about ¼ inch of plastic from the ends of the AWG18 gauge wire using wire strippers. This exposes the inner copper wire that attaches to the LR41 batteries.
- 4). Attach one end of one of the wire strips to the negative terminal of the first LR41 button cell battery in the row. Use a small strip of electrical insulating tape to hold the wire onto the terminal. The negative terminal is on the base of the button cell and is the raised, slightly rounded end. You can easily tell because the opposite side has a large "+" marked on it.
- 5). Attach one end from the second strip of wire to the positive terminal of the last LR41 battery in your row of batteries. Use a small strip of insulating tape to hold it in place.
- 6). Put the negative terminal of the second battery in the row directly over the positive terminal of the first battery in your row. You need to arrange the batteries in a pile. Repeat the process of carefully placing each battery in the row on top of each other in the same way, ensuring all the positive terminals face upwards.
- 7). Wrap electrical insulating tape around the pile of batteries so you hold them in place. Put the last LR41 battery that has a wire attached on top of the pile, ensuring the wired positive terminal is on top.
- 8). Wrap more insulating tape around the entire pile of batteries to keep them together, then finally wrap insulating tape over the two wires attached to the positive terminal on one end and the negative terminal on the other. Your LR41 button cell batteries are arranged in series and produce the voltage necessary to power your device.
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