For LED builders -- NiMH batteries with solder tabs

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Looks like a good deal, I have no affiliation with the guy.

http://cgi.ebay.com/aw-cgi/eBayISAPI.dll?ViewItem&item=182073579

-- Ron Schwarz (rs@clubvb.com.delete.this), October 22, 1999

Answers

Forgot to mention, they should be good for all sorts of things besides LED lamps.

-- Ron Schwarz (rs@clubvb.com.delete.this), October 22, 1999.

NiMH batteries have a ferocious self discharge rate, be advised. You would not want to store them and expect them to be useful after being in storage a couple months. Personally I'd stick to nicads. Panasonic makes Nicads in 1100mah capacity and I hear Sanyo has 1200's. Memory isn't such a big deal with todays nicads..besides you can drain the batt and recharge it a couple, three times and overcome any memory effect.

DCK

-- Don Kulha (dkulha@vom.com), October 24, 1999.


I've had good luck using NiMH cells in day to day situations, and for certain applications they're irreplacable. For example, our Cherokee FR-465 radios perform better on the factory NiMH packs (that we finally broke down and ordered) than they do on the higher MAH alkalines, because the high discharge rate prevents the alkalines from ever reaching their rated capacity. Self-discharge (which is faster than Nicad's rate) isn't an issue, as we're not charging then storing them.

However, because the radios use AAA cells, there would be a serious problem using Nicads, as AAA Nicads are *very* puny.

If you're storing something that you want to be able to unpack and use, then don't use *any* rechargable battery, because whether you're using Nicad of NiMH, the self-discharge rate will get you. Use alkaline or lithium for storage, and rechargables for day-to-day usage.

BTW, there are some nice 1.6AH sub-C Nicads w/solder tabs at http://cgi.ebay.com/aw-cgi/eBayISAPI.dll?ViewItem&item=183219044. I'm hoping to get some of 'em myself, looks like a good deal.

-- Ron Schwarz (rs@clubvb.com.delete.this), October 25, 1999.


Argh, I hit the button too soon. Got them raging-headache-bonespur- neckjoint-blues.

My point I was trying to make is that where NiMH cells really shine is in the power density department. We recently picked up an older (full size) Midland UHF HT at a very good price, with a basically dead battery pack. It had a bunch of Nicads that were past the end of their lifespan. Three were sort of OK, but three were plain ol' dead. They were top-quality cells, Sanyo Cadnicas -- "fat AA" size, 800 MAH. I gutted the battery pack, put in some off-the-shelf Toshiba NiMH cells I had laying around, and it works fine. More than 50% greater capacity in a smaller package.

-- Ron Schwarz (rs@clubvb.com.delete.this), October 25, 1999.


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