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0 pointsZak1y ago0 comments

Yes. The Sony VTC6, for example is rated to deliver up to 30A with temperature monitoring to ensure it doesn't exceed 80C. At 3.0V (partially discharged and with voltage sag from the load), that's 90W.

I don't actually need 90W in the application I have in mind. I'd be more than happy with 60, and there are quite a few 18650 cells that can do 20A comfortably. Runtime at full power would be short of course, but I don't find I'm continuously heating work for very long in the field.

Here's a test of the VTC6. It does look like it's struggling a bit at 30A, but it's happy at 20. https://lygte-info.dk/review/batteries2012/Sony%20US18650VTC...

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kube-system1y ago· 2 in thread

> Max. discharge current vs. time: 30A-40A > 44s

I figure that might be workable for a few power cycles and a few big solder joints, but it would probably be a frustrating experience for anything more than quick fixes in the field.

Kirby641y ago

If you're using full power for longer than 40 seconds, you're almost certainly doing something wrong (or, need to switch to a chunkier soldering iron). At a certain point, the limiting factor becomes how quickly you can transfer heat from the iron into the solder, and you won't pull 100W anymore.

I have a JBC iron capable of 130W. It never pulls 130W, even on extremely chunky power planes, besides when initially heating up (on startup). When trying to heat some super thick, I can watch the power meter max out at ~70W (and it pulses 70W, not continously). And this is on a thick tip, far chunkier than what I see from iFixit.

kube-system1y ago

Yeah, I didn't mean to suggest that someone would do that whole 40s all in one go... maybe a handful of seconds of full-power here and there... but heat accumulates and people probably want to put the iron down well before the battery in the handle hits its thermal limits. It just seems to me like it would be a good candidate to get hot quickly and suffer in both performance and comfort due to it. I'm sure it would probably be perfectly fine for light field use.

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