I jump-started a bus from the 1930s with this power bank – here’s the verdict

I test a lot of power banks, and the amount of energy being crammed into these small devices is becoming incredible. Now, they’re making small handheld units that can’t just recharge your smartphone or tablet, but can actually start vehicles. 

Also: The best power banks you can buy in 2025

While these portable jump starters are designed for normal cars and trucks, I thought I’d give the Gooloo GT6000 a test — starting a 1936 Albion SP PV70 coach, one of the many vintage vehicles at the Anglesey Transport Museum here in North Wales, UK (and yes, it still drives!). 

The GT6000 is as big as power banks get, housing a 27,000mAh/99.9Wh battery. It powers a 100W max in/out USB-C port, an 18W max USB-A port, a 12W USB-A port, and a 150W DC output port. Using a 100W USB-C charger, you can take the unit from flat to 20% in seven minutes and to fully charged in under 90 minutes.

The unit can hold its charge for a good two years, so you can charge this up, throw it in the back of a car, and have it ready for an emergency. 

It can also push 800A starting current/6,000A peak current to the car jump leads. That’s enough power to start pretty much every gasoline engine out there, and diesel engines up to 12 liters. So while the six-liter Albion engine is small, it’s an old, heavy engine, and the battery on the coach was totally dead. 

Also: 3 portable power stations I travel everywhere with (and how they differ)

The GT6000 has a 3.2-inch LED screen that shows the basics: battery capacity, charge/discharge rate, and whether the unit is ready to jump start a vehicle. The display has a matte finish that works really well in both bright sunlight and subdued conditions.   

So how did it hold up? The GT6000 had no problems whatsoever. Don’t believe me? Check out this video. 

In terms of durability, the unit is super robust, capable of taking quite a beating, and also IP65-rated for dust and water-resistance (totally dustproof, and capable of withstanding rain and splashes). The GT6000 has a built-in LED light too, perfect for when disaster strikes at night. 

ZDNET’s buying advice

I’m very impressed by the Gooloo GT6000. It combines a massive power bank with a very capable jump starter. I’ve tested this with a number of vehicles, but the speed at which it got that old Albion going really surprised me. This can push a lot of current to a vehicle, and does so very reliably (that old bus needed a few restarts during its journey as it stalled a few times!). 

It’s definitely something that’s being added to by workshop kit.