Using a lithium jump-start pack to power a trailer winch

[this is my username]

I have a trailer used to haul lightweight (c. 300kg) wheeled vehicles. I currently use a hand winch, but an electric winch with remote control would make single-handed loading much easier.

I can buy a small electric winch for c. £150 - so far so good. The trailer is used on multiple vehicles so hard-wiring a power supply on the vehicle(s) isn't a good option. The trailer is only used a few times a year and is parked well away from any power source so a dedicated battery on the trailer isn't an easy solution.

Quite a few people seem to use jump-start battery packs - portable, don't need installation, can be taken away to charge, so all good. All the users I can see online appear to be using "old-school" lead-acid packs. I would prefer to keep the size and weight down - has anyone tried powering a small winch from one of the modern lithium jump-start packs?

[bangerhoarder]

I *think* that’s a recipe for fire, or at the least a very dead battery pack. They’re designed to put out a large spike in current (CCA) and not a high continuous output. That battery pack may be 5Ah, where a lead acid battery can run the motor for far longer comfortably (small ones around 40Ah or less for motorbike batteries) (depending on size).

[Darkslider]

bangerhoarder said:

I *think* that’s a recipe for fire, or at the least a very dead battery pack. They’re designed to put out a large spike in current (CCA) and not a high continuous output. That battery pack may be 5Ah, where a lead acid battery can run the motor for far longer comfortably (small ones around 40Ah or less for motorbike batteries) (depending on size).

Came here just to say this, the reason you only get 5 seconds cranking time with the small Li-ion packs is that's all they're safely capable of delivering in one go without overheating. I've got 2 or 3 and they all seem to require disconnecting from the unit and reconnecting in between goes before it'll give you another shot, I've always assumed this was intentional to give the pack a break, but it does mean it'd be very tiresome winching a vehicle on in 5 second bursts with one.

[this is my username]

Thanks for the replies. That's what I was worried about. Will probably try it with my existing (small capacity) lithium pack and see what happens before I commit to anything ....