<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML><HEAD>
<META http-equiv=Content-Type content="text/html; charset=iso-8859-1">
<META content="MSHTML 6.00.2800.1400" name=GENERATOR>
<STYLE></STYLE>
</HEAD>
<BODY bgColor=#ffffff>
<DIV><FONT face=Arial size=2>I have been working in the battery area for 40 +
years so let me pass on my knowledge. When the Duralites first hit the
market I went on line and said "<STRONG>Be very careful with these solid lithium
anode cells</STRONG>"- they can vent catch on fire etc especially after repeated
cycling. The reason for this is after several charges the lithium forms
Dendrites (spikes on the surface) which punch through the separator and short
out the cell. No one paid any attention to this. Now in the case of
the Lithium-Ion these cells <STRONG>DO NOT LIKE TO BE OVERCHARGED.i.e. above 4.2
volts.</STRONG> They will vent and catch on fire. I use them in flat
packs but each cell has a protective circuit on the cell and can be charged at
constant current using a standard charger at 250 mA. When any cell in
the two cell pack reaches 4.2 V the protective circuit on the cell senses this
and takes the cell off line, hence the battery of two cells off charge.
Yes these battery packs are a bit lighter and have a higher energy density
(Wh/kg). Let me pose this, Nickel-cadmium cells are a proven technology
and can be fast charged safely and work. Why not stay with they. The
Nickel-metal hydride is a good system. However, it looses capacity on
stand, and requires careful field charging to prevent it from getting too hot
and venting. Also it does not work as well at low temperatures. My
advice stay with Ni-Cd.</FONT></DIV></BODY></HTML>