Using a battery-powered booster pack is the safest way to jump start a car because it eliminates the possibility of sparks and alternator damage. But the lead-acid battery inside the pack doesn’t last forever. When the battery inside your booster pack stops working, you can rebuild it yourself for a fraction of the price of a new one.
You’ll need a 6-in. Phillips or star bit, a drill and a 1/4-in.-drive socket or nut driver set. Once you open the case, remove the battery and match it up at a local auto parts or battery store. If you want to order a replacement online, measure the battery’s overall size and note the terminal style and amp-hour rating. Our replacement battery cost about $35 online.
To replace your battery, start by removing the decorative trim pieces and screws (Photo 1). Then separate the case and swap the batteries (Photo 2). Reassemble the case and charge the battery until the charge light turns green. The booster pack can now be used for jump starting a dead car battery.