Natural Science Forum / Chemistry / Electrochemistry / May 2006

Hey everyone,
I just recently bought a Dirt Devel micro-vac...  The kind you use to clean
keyboards.
Well I normally stay away from rechargables - especially NiCd because of

I have a standalone charger for some AA (and AAA) cells when AA cells
held about 500 to 600mAH.
The charge rate is a steady 150 mA (50 mA for AAA) and there is no cut-
off mechanism.  The charger leaflet recommends 5 hours for cells between

Greetings All
I have a question dealing with electrolysis and lasers the text books
say you need 1.25 electron-volts (eV) or 2.002 x 10 - 19 Joules to do
electrolysis with water.  A small pen laser puts out about 5mW which is

I have two electrodes bias (15VDC) in a water solution (in water Pt is
inert), with the assumption there are no contaminates in the water, and
the Cu is the anode and Pt the cathode.
Then Cu2+ will migrate from the anode to the cathode and OH- will

Does anyone know of commercially available electric scooters/bikes that
use Lithium Ion batteries?  I'm looking for one that is light, can do
0-40MPH in 10 seconds, top speed 70MPH and 100 mile range on one
charge. Does such a beast exist?

Don't try this at home, but if you think microporous polyethylene is a
necessary component of a flow cell, think again:

I have a rapid charger with a fold down cover.  When I charge a couple
eof AA or AAA cells there is a smell of gas in the chamber under the
lid.
Seems to me that the cells are getting overcharge and are venting.

I'm told that an ESR (equivalent series resistance) meter can be used for
measuring resistance of cells, an indication of cell life expectancy. Of
course this is only if the meter has high input impedance and is not
diode-protected.

Hi, is there some kind of batteries that cann be shaped like clay. I nead 48
v/10 Ah bateries, specific shape. Something like triangle (30 cm *  30 * 30
cm  - cca), 3 cm deap.
Any ideas?

I am looking for battery selection advice for a catamaran hybrid
propulsion system.  There are 2 48 VDC 10 KW motors plus house loads of
up to 6KW.  The 2 electric motors are capable of regeneration while
sailing (perhaps a max of 1 KW), a 16 KW DC generator, 200W solar

From:        Jean-Marc Delaplace - view profile

I'm a bit nervous about doing some traveling.
I will be using a power inverter to power electronic equipment.
I never want to be stranded because of a dead battery, So I started
searching for options.

I need to charge a device with a Li-Ion battery that, according to its
label, expects a 5V 2A power supply. Unfortunately the only car lighter
power supply I can find with the correct jack is rated 6V 500mA.
Is this safe to use or will I damage the battery/electronics?

Which chemistry gives higher capacity relative to the rated capacity at
1C rate discharge in -20 to 0°C range?  I seem to recall NiMH did quite
well in that temperature range up around 1C discharge rate, but rapidly
degraded once discharge rate increased.

I have a pair of golf cart batteries powering a small (@300 watt)
inverter for emergency lighting.  Normally there is no external load on
the invewrter except for a tiny neon light, but of course the inverter
draws some load by itself.  What is the best way to keep the battery