Dead Nikon Batteries Revived

[axle01]

Hey guys I had #4 ENEL4 batteries for my Nikon camera and over the years 3 have died, so I’m now down to 1 battery.
I looked on B&H site and a genuine Nikon battery is $110 US plus postage to Australia so I’m thinking about $170 AUD
A cheap one on eBay is about $60.
I thought I would open one up and see what's inside and I was surprised to see that there was 3 x 18650 batteries which I have about 30 of.
So got out the soldering iron removed the 3 dead cells and soldered in 3 new ones.
Took a bit of time and being very careful not to touch the circuit board with the hot iron but now I have 3 batteries and I’m going to do the 4th when I get time.

[arthurking83]

.....
I thought I would open one up and see what's inside and I was surprised to see that there was 3 x 18650 batteries which I have about 30 of.
.....

Yeah, the larger D single digit battery packs use 18650 cells .. easy peasy.

Wish it were so with the more usual consumer bodied cameras tho. It ain't!

I pulled apart one dead old EN-EL15. The cell used in these consumer model EN batteries use is not standard. Hard to find cells at a decent price, so not worth rebuilding.
I ended up dumping it all. Hard part is separating the case to start with. I'll have to play with another dead one I have from the D70s too.
I didn't catalog any of the info, and can't recall the cell size. About 3/4 the length of the 18650.
Good aftermarket batteries for these model cameras are relatively cheap(~$20), so not worth the effort. Interesting for the purpose of education tho.

just one other point(been there done that). I don't solder any lithium battery any more, and now heed the now warnings on doing so that I previously ignored.
The heat that the solder needs to flow is way too high for a lithium cell when directly attached. OK if the solder is on a tab .. but never on a battery end.

I refurbished an old power tool battery(Ryobi One). It was a lowly 1 or 2 Ah battery that wouldn't hold charge. Used a few of my 18650 stash(I think 6 .. can't remember). Soldered up, no worries ran drill. Ran drill under load for a few seconds and then pixie smoke started to escape the battery case!
It was a few years ago, so can't remember all the actual details .. but of the 6 cells I did, one got so hot it melted itself. Lucky it didn't catch fire. The heat of the solder must have killed that one cell internally and under load it went nuclear.
The huge difference between that experience and your Nikon freshen up is that the drill was under a much hard load, when a battery shows it's true ability.

Despite some of my caveats and dire commentary above .. still good to see this sort of stuff.

[axle01]

I don't solder any lithium battery any more, and now heed the now warnings on doing so that I previously ignored.
The heat that the solder needs to flow is way too high for a lithium cell when directly attached. OK if the solder is on a tab .. but never on a battery end.
:

I use solder flux on the tab and battery then add solder to the tab and to the battery end.
Using the flux the solder flows and sticks really fast without much time with the hot iron in contact with the battery.
But if in doubt don’t try this at home.

Al