The Natural Philosopher wrote:

And can your cordless keep that up for two or three hours to section a
full sized tree?

I only nip down and do a couple of hours worth at a time to get rid of
the tree, the section of trunk was [guestimating] a few hundred kilos,
so levering it about to avoid the saw touching the ground takes a lot of
time, the saw's not running for long periods, but I'd expect it to need
maybe a set of batteries per hour if it was.

On 02/05/2021 09:16, Andy Burns wrote:
The Natural Philosopher wrote:

And can your cordless keep that up for two or three hours to section a
full sized tree?

I only nip down and do a couple of hours worth at a time to get rid of
the tree, the section of trunk was [guestimating] a few hundred kilos,
so levering it about to avoid the saw touching the ground takes a lot of
time, the saw's not running for long periods, but I'd expect it to need
maybe a set of batteries per hour if it was.

Same here. I don't see tree surgeons and full time wood-cutters giving
up on petrol for a while. But for more casual DIY use, especially if you
are getting on a bit and don't have to finish in a day, even an 18 volt
lithium is an eye-opener. And since I have standardised on one make, I
have three or four 4AH and two 2AH batteries; I suspect they'd be enough
for a full day even without recharging.

newshound wrote:

I don't see tree surgeons and full time wood-cutters giving up on petrol
for a while. But for more casual DIY use [...] 18 volt lithium is
an eye-opener.

I'd say that's a fair summary.