Re: (ET) Why lead acid batteries need high current charge.

["David Roden" <etpost drmm net>]

This is an intriguing explanation!  I think I can actually understand it.  
;-
)

It inspired me to dig though some of my old email and find a message from 
Nawaz Qureshi, an electrochemist at US Battery.  This is his attempt to 
explain why Hawker batteries need at least some high current charging to 
maintain capacity.  I think when he says " grid-active material barrier 
layer" he means that there is a barrier of some sort between the grids and 
the active material that they hold. Although he says this applies to AGM 
batteries, and not to flooded batteries, it certainly sounds like a first 
cousin to what Dr Meissner is saying.

"Blasting AGM's with 2C to 3C rate at the start of the charge, if you can 
do
it, just for a few seconds, tends to break up the grid-active material 
barrier
layer in the positive plates resulting in the prevention of loss of 
capacity
owing to this layer that is peculiar to the AGM's if you deep cycle them. 
It
is beneficial."

Batteries are fascinating creatures, aren't they?  

I wonder what sex they are. ;-)


David Roden - Akron, Ohio, USA

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