How to Build an External Battery Pack for Laptops
- 1). Check the required power your laptop needs to operate. This is most important before you attempt to build your external battery pack. You will find the voltage clearly labeled on the reverse of your laptop. Most laptops require about 19 volts, which means you need five LiPo cells wired in series. Wiring in series combines the voltage from each cell.
- 2). Lay your batteries together on a flat surface with the terminals alternating. If you're using five batteries you have three positive and two negative at one end and three negative and two positive at the other. LiPo batteries are similar in shape to regular AA batteries but are a little shorter and fatter.
- 3). Label your batteries numerically, so if you're using five, label them 1 through 5. Wrap electrical insulating tape round the batteries to form a neat tight external laptop battery pack.
- 4). Cut strips of wire using a knife; AWG 16 or similar is fine for a laptop battery pack. Two strips need to be long enough to comfortably reach your laptop while the other strips only need to connect between the battery terminals. Work out the number of short strips you need by simple deducting one from the number of batteries you are wiring. If your are wiring five batteries you need four short strips.
- 5). Remove 1/4-inch of wire from the ends of each strip to expose the inner metal wire using wire strippers or a small knife. Attach a long piece of wire to the positive terminal of battery 1 using a strip of insulating tape. Label the wire "+." Attach the other long strip of wire to the negative terminal of your last battery using the same method and label the wire "-."
- 6). Attach a short strip of wire to the negative terminal of battery 1 and attach the opposite end to the positive terminal of battery 2. Repeat the process by attaching short strips of wire to the negative and then positive terminals in numerical sequence until your last strip of wire attaches to the positive terminal of your last battery.
- 7). Wrap the complete battery pack in electrical insulating tape. Ensure you completely cover all the terminals, but remember to leave the two long wires exposed as these need to attach to your laptop.
- 8). Obtain a laptop power jack. You need this to connect to your laptop. Visit an electrical store and take your existing charger with the power jack so you get the correct one. Alternatively take your laptop to the store.
- 9). Remove the cover from the power jack and insert your two longs wires through the cover ensuring the threaded end faces the end of the wires. The central metal part of the power jack has two terminals labeled "+" and "-." Use a soldering iron and solder to solder the wire you labeled "+" to the positive terminal then solder the wire labeled "-" to the negative terminal. Slide the cover down the wire and screw over the power jack. Your external laptop battery pack is built.
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