In article ,
T i m wrote:
On Mon, 10 May 2021 00:35:35 +0100, "Dave Plowman (News)"
wrote:

snip

Try leaving one for six months. Also, I bet most of these contain
bargain basement batteries.

Are you saying a Li-Ion one - which starts off with less capacity

Whilst it may start off with less Ah capacity, it may well have a
greater cold cranking current so more likely to start a car, assuming
it's willing to start easily.

Cold cranking is the one to look for. Looking at specs for these Li-Ion
packs, they seem to do anything other than quote in the same way as you'd
expect with a lead acid battery. I'm sure it's not a problem with a small
engine, but can be if looking for one which will cope with a bigger one
and maybe diesel.
- is
going to be fine after 6 months, like for like?

Yes.

I'd say most Li-Ion jump
start packs ain't got the finest either, by the price.

But I'm not sure they need to, given what sort of CCA even low spec
ones can output.

But for how long? They all seem to be much lower capacity than the older
lead acid jump packs. Not a problem if the engine starts instantly, but
this may not be the case with an engine where a start was attempted with a
very low battery and failed - hence needing the jump start.

If you want a bit of a rambling redneck overview of a LA V Li pack
(all be they way different prices):

https://www.youtube.com/watch?v=PwA78cGULDY

Cheers, T i m

--
*Many hamsters only blink one eye at a time *

Dave Plowman London SW
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