baterry questions

[Carlos]

Hello:
Can somebody tell me which the difference is between a charger of batteries of lead acid gel and an of nickel cadmium?
Thank you

Carlos

[graeme]

Hi Carlos,

There are many theories/thoughts upon battery charging.

For the past few years I have used a design - originally for gel-cell acid batteries - on both types. The gel-cell apparently needs a trickle-charge to bring cell-voltage up, before
subjecting the battery to full-charging current.

I have found that many discarded gel-cells can be "brought back". The circuit comes from "Silicon Chip" - an Australian magazine - and uses a device manufactured by Unitrode - the
UC3906.

This device - although expensive - measures initial cell voltage - trickle charges to a higher voltage - switches to a pre-settable heavy current charge - charges to a pre-determinded level of cell-voltage - then switches to a "float-level" of charge. That allows the battery to remain connected to the charger - with no chance of over-charging damage.

The circuit provides switching for either 6volt or 12volt batteries, and for batteries rating from 1.2aH to 15aH.

The article (ten pages) provides a circuit-board lay-out.

If you, Carl, or anyone-else is interested in a copy of this article, then E-Mail me with a postal address. Sorry, I do not possess a scanner.

[graeme]

Sorry!! Just realised my address was incorrect!!

It is -

graeme_smithson@xtra.co.nz

g.