replacing batteries in Norelco shaver

| IT WORKS ALREADY READ MY FIRST POST .

So? We have to stop discussing it? :)

"Jim Yanik" bravely wrote to "All" (25 Aug 05 23:17:16) --- on the heady topic of "Re: replacing batteries in Norelco shaver"

JY> From: Jim Yanik JY> Xref: core-easynews sci.electronics.repair:340643

JY> NiMH cells have a more complicated charge requirement than NiCd. JY> Unless you plan on designing a new charger,you should only replace JY> with NiCd cells similar to what you removed.

Riding my bike I found a cellphone flattened by traffic on the side of the road. Its Li-ion battery seemed undamaged and it took a controlled charge okay. I was thinking of replacing the 2 sub-C nicads in a hand driver with it, as the Li-ion cell has a 1,000mA/hr spec on the label. It seems impossible for such a small battery (2"x1.5x1/4"thick). There are 3 contacts on the cell, beneath is a pcb with surface mount IC's. One terminal is labelled TH, what is it, thermal monitor?

A*s*i*m*o*v

... That was a fascinating period of time for electronics

"Asimov" wrote in news:MSGID_1=3a167=2f133.0 snipped-for-privacy@fidonet.org:

I don't know what the "TH" means.Possibly "THermal",maybe a thermistor for temp monitoring. You could try measuing resistance between TH and each other terminals,perhaps while changing the packs temp by hairdryer.

Wood Magazine recently had an article on a new drill/driver that uses Li- Ion cells in a 28V pack with a microprocessor controller IC built into each battery pack,it not only controls the charge,gettting the most from the cells,but it counts charge cycles and keeps track of battery life.According to the article,some Li-Ion formulations do not have a high discharge current capability,that it shortens cell life.But Milwaukee says their cells are different.Their cells are 4 volts apiece.(Is 4.8v/cell 'standard' for Li-Ion?)

I put NiMH cells in mine a year ago...

I let it charge a bit longer, as the capacity is much higher...

Works great!

Did the same with my Uniden and Panasonic cordless phones. I let 'em charge fully, and they last a l-o-n-g time!

And I didn't redesign the charger. These are trickle chargers, gentlemen.

A fast charger would matter... These do not.

IMHO...

Jack :)

Li-ions can only be at best pulsed at a 2-3C rate. The TH probably is the termistor and the pcb has picofuses. How will you charger it once in the driver? Li-ion aren't for casual experimenting, as you no doubt know..

This has a nice update on consumer product Li-ion capacities.

"H. Dziardziel" bravely wrote to "All" (30 Sep 05 09:53:52) --- on the heady topic of "Re: replacing batteries in Norelco shaver"

HD> From: H. Dziardziel HD> Xref: core-easynews sci.electronics.repair:343591

HD> Li-ions can only be at best pulsed at a 2-3C rate. The TH probably HD> is the termistor and the pcb has picofuses. How will you charger HD> it once in the driver? Li-ion aren't for casual experimenting, as HD> you no doubt know..

The battery has its own charging smt electronics on a tiny board that holds the contacts for the adaptor base. I would connect the existing driver terminals to these contacts and not directly to the battery.

I was so impressed by an experimental electric sports car I saw on Alan Alda's science show. It went 0-60 in 3.2 seconds and a top speed over 200. Consider that not many gasoline powered cars can do that. It was powered by a bank of Li-ion batteries. It must be quite breathtaking to press the accelerator sitting in that car. Oooh, the G's, the G's!

A*s*i*m*o*v

... Wasted power is current squared times the resistance.