Re-cell old DCS 560/660/760 packs with Li-ion cells?

Discuss older Nikon-based Kodak digital SLRs, including DCS 100, DCS 200, NC2000, DCS 400/600/700-series, etc. Ask questions, post general comments, anecdotes, reviews and user tips.
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spacespeed
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Re-cell old DCS 560/660/760 packs with Li-ion cells?

Post by spacespeed » Wed Feb 15, 2012 11:17 pm

Hello everyone,

An odd idea came to me about a week ago. In theory, would it be possible to take apart old DCS 560/660/760 battery packs, and replace the NIMH cells with Li-ion cells? 2 3.7v li-ion cells have about the same voltage as the Sub-C cells that are used in the packs, and the 14500 might just fit into the packs. Charging would be via some universal charger that can handle li-ion cells. Primary issue is that their capacity is apparently quite a bit lower - I guess one could wire some of them in parallel, but there's not that much space inside a pack. Another would seem to be that their voltages seem to fluctuate a good bit - fully charged, two of them would be at 8.4v.

Primary reason? Good NIMHs are getting harder to find, and I seem to have a semi-damaged 3rd-party battery pack - all of the contacts to the outside work, but one of the internal contacts came off - while I managed to solder that back on, the camera doesn't seem to like this very much, and will act up randomly as a result - refusing to read memory cards, etc.

Any thoughts?

Multifot
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Re: Re-cell old DCS 560/660/760 packs with Li-ion cells?

Post by Multifot » Sat Feb 18, 2012 6:46 am

Re-celling is not cheap if you will quote a special company. Also it hard to do by yourself due to re-celling require spot-welding machine to weld cells with metal strips. New "made in china" Ni-Mh pack for DCS 760 costs me only 13.00 USD with free shipping to Russia 4 month ago. It is cheap. Buy 5 units and you will have good fresh power reserve. Also you can try to use external power pack like Quantum.

Multifot
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Re: Re-cell old DCS 560/660/760 packs with Li-ion cells?

Post by Multifot » Sat Feb 18, 2012 6:46 am

-- sorry, it was double --

Stan Disbrow
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Re: Re-cell old DCS 560/660/760 packs with Li-ion cells?

Post by Stan Disbrow » Wed Feb 22, 2012 4:16 pm

Hi,

Nope. Not a good idea. LiIon cells require specific charging profiles, and the Kodak charger won't provide those. So, you'll pop the LiIon cells in a hurry, and sometimes popped cells catch fire....

If you think on it, there are always products in the news where they have LiIon battery issues that cause recalls. This is with proper charging profiles and controllers that are only a little 'off' the mark. It gets worse if you don't have anything like a proper profile....

Essentially, you have to watch the voltage change rate, the current change rate and the temperature change rate all the while the pack is on charge. Those constant readings are compared to a charge profile curve stored in memory for the cell (a LiIon pack has a built-in processor and memory to do this with, talking to the charger via a serial data bus). The processor adjusts the charge voltage and current in real time to hold the pack on the curve.

The Kodak stuff does none of this. So, you'd have to use a generic LiIon charge controller hooked to a bench power supply to do this. They cost over $500, so this isn't worth it unless you're going to deal with a lot of different LiIon and LiPolymer packs for other uses.

Later!

Stan
Amateur Photographer
Professional Electronics Development Engineer

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