Li-ion

[panserv]

Hi everyone, I just stumbled on this site while searching for information about li-ion batteries.
Not too long ago, before Li battery tech came along, I commissioned mobile radio systems for utilities.
Now I have been asked to look into setting up a P25 digital radio system for a medic volunteer agency, using Motorola Astro Saber portable radios. These radios though obsolete, can still give excellent service, provided they have battery power of course.
My idea was to junk the old ni-cad packs and install new x2 Li-ion 18650 cells.
Because I am not familiar with Li chemistry support, I have a few stupid questions to ask.
I looked for charger boards for Panasonic NCR18650B, 3400mAh cells and came up with Protection Charger boards like

http://www.ebay.com/itm/Protection-...92?pt=LH_DefaultDomain_0&hash=item3cc4cb3708.

It sounds good, because with 2 cells + this board in the pack, you get charge balancing, and charge/discharge protection.
However I am concerned that with this arrangement, the charging voltage of 9v will be present at the battery terminals. This is the absolute max supply voltage the radio can tolerate, way too close for comfort.
Is there a way around this?
Maybe using a different board type, with separate charge input and battery output terminals, but I cant see any.
Would appreciate some expert help here thanks.

 

[itsmoked]

I think you are would be making a BIG mistake changing the battery type in a custom handheld radio. The radio was designed around the original battery chemistry. You will have lots of problems switching them and problems can result in the users being let-down. NiCads are great batteries! Just don't eat them. They also won't catch fire if you do the wrong thing once. With Lithium batteries all you have to do is over discharge them once and you have created a ticking problem that can strike anywhere down the road as a fire.

Keith Cress
kcress -

http://www.flaminsystems.com