On 11/8/20 1:27 PM, Jeff Liebermann wrote:
On Sun, 8 Nov 2020 08:12:19 -0800 (PST), "Peter W."
wrote:

https://www.wish.com/product/5a71225..._wcB&share=web

This is the same battery connector for R/C cars, boats and planes. Capable of up to 25A at 7.5 volts.
Should do the trick.

Peter Wieck
Melrose Park, PA

Ham radio has the same problem and has mostly standardized on Anderson
Power Pole type connectors for 12V power:
https://www.google.com/search?q=anderson+power+pole&tbm=isch
Personally, I hate these, but I must admit that they do work well for
high current applications.

What I prefer are XT60 60 amp connectors used by RC enthusiasts for
LiPo cells:
https://www.google.com/search?q=xt60+connector&tbm=isch
https://www.ebay.com/itm/132200748004
They are also available in 30 amp (XT30) and 90 amp (XT90). Note that
these are intended to be soldered, not crimped.

Back to the original problem. The cigarette lighter connector was
never intended to power anything continuously. It wasn't even
designed to maintain a reliable connection. It's the only connector
which has a spring that pushes the plug *OUT* of the receptacle
instead of pushing it in or locking it in place. To make matters
worse, there is usually a fuse behind the tip, with a marginal spring
connection and insufficient fuse connection clips. Just count the
number of crimps, connections, rivets, and dissimilar metals that the
current has to go through and you'll see why it might be getting hot.
At 5V 7.5A, it doesn't take much resistance to create an unacceptably
high voltage drop. Try measuring the voltage drop under load across
the entire connector sandwich. I don't think you'll be too happy with
your measurement.

Yeah, this one was pulled off of an unused auto inverter. On the plug
is says to not draw more than 100 W through it and it has either 12 or
14 gauge pigtails with a 10 amp fuse inside the plug. I know it must be
pretty lossy since it is heating up more than anything else in the
circuit.

I like the XT60 connector you mentioned after checking out its specs. I
think that's the one I'll go with when I order tomorrow. And I do like
the fact that it is solder and not crimped. I don't always trust
crimped connections. I know it's probably my fault since I don't often
have the correct crimping tool so when the wire works out, that's why,
but soldering with circumvent that issue. Thank you.


There have been attempts to standardize the cigarette lighter
connector as ANSI/SAE J563:
https://en.wikipedia.org/wiki/Automobile_auxiliary_power_outlet
The problem is that most commodity connectors don't even come close to
meeting the specifications. I think that's the cause of the heating
problem that you're experiencing.

Good luck.