With a 27,800-mAh capacity and a 4,000-amp peak, this Avapow portable jump-starter packs some serious power. It can start any vehicle with a gas engine, or any diesel engine up to 10 liters.

If a jump starter lists cranking or cold-cranking amps, you’ll need to meet various thresholds to power your car battery. If you don’t want to consult charts and can afford them, you could ...