I was interested in your question because I had never heard of
"deep-cycle dry cell" batteries, so I went looking... I have some
experience of applications requiring extreme battery dischage.
It seems that the technology of these "dry cells" are what I know of as
"gel-cells" which are still Sealed-Lead-Acid (SLA) batts, but are
designed to be invertible and not to leak if punctured, they are also
completely sealed, with special valving to allow gaseous exhange.
They also have extremely high short-circuit current ratings (also known
as cold-crank) - much higher than the DeLorean starter will ever draw,
and the ability to provide high currents for long periods while
maintaining an acceptable level of efficiency. On all these points,
you're better off buying the biggest off-the-shelf standard SLA and
paying a third of the price - just make sure it has a decent cold-crank
rating.
For further reading, may I suggest you look at www.hepi.com - Hawker
Energy make the world's best gel-cells, but even they only have an
efficiency of 45% at maximum continuous discharge. I looked at using a
Red-Top 50 in my DeLorean but the cost wasn't justifiable when the OEM
AC-Delco batts are available over here for about £45
There are now true dry-cell batteries capable of more than replacing
SLA's but they cost a fortune, and are only in pilot production. (Our
robot runs on a set - we are sponsored by the manufacturer)
Martin
#1458
Digital Devices wrote:
Worth the extra money or better to stick with your run of the mill
battery?