In article ,
Bert lijbertv_at_xsinet_dot_co_dot_za wrote:

----- Original Message -----
From: "Gerard Bok"
Newsgroups: sci.electronics.repair
Sent: Sunday, March 05, 2006 1:44 PM
Subject: Alkaline charging followup


On Sat, 4 Mar 2006 21:50:42 +0200, "Bert"
lijbertv_at_xsinet_dot_co_dot_za wrote:

December around the 21st last year I did have a question on charging a
rechargeable alkaline AA battery.
Using those 2 in my wireless optical mouse.
Normal battery did last 1 month
Alkaline battery did last 5 month,
Alkaline recharge battery 2.5 month, empty reading is 1 volt.
Started charging both batteries on 1.68 volt, the charging current was
110
mA per battery.
Charging current after 10 hour is 95 mA for both batteries, constant
voltage
1.689 volt.
Hope this will help someone sometime.

And the number of spontaneous exploding charging cells is still
zero, I guess ?

--
Kind regards,
Gerard Bok

No exploding cells, do check every hour or so that the voltage on the
battery stays below 1.7 volt and the battery is still cool to touch.
Remember it is a rechargeable AA alkaline cell.
Greetings
Bert.

Seems like a lot of babysitting effort just to recharge a battery. Are you
doing this as an intellectual exercise, or do you really plan to keep this
going? This is why the commercial chargers used for RAM cells are controlled
by dedicated circuitry. The batteries are pulse-charged, and the duty cycle
is
controlled by the voltage of each individual cell as read in between
charging
pulses. As the voltage of the cell approaches 1.65V, which is the defined
terminal voltage for a RAM cell, the duty cycle of the charging pulses
approaches zero. Trying to replicate this, over several hours, by manual
checking against a constant-voltage source sure seems like a lot of work.


Mike S.
You are right about the babysitting, just wanted to see how many hours are
needed to a full charge, it is around 24 hours.
I will make sometime a pulse charger, keeps me busy.
Greetings
Bert.