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Re: (ET) Batteries



If you're measuring an SG of 2.2, either you're reading your hydrometer 
incorrectly or it's inaccurate.  Typical SG range is 1.1 to 1.3.  A fully 
charged 
battery should measure 1.28 or so when new, perhaps 1.25 or so after a few 
years.  The declining SG with age is an (but not the only) indicator of 
declining capacity.

Your big voltage sag when you apply a load indicated high internal 
resistance.  This is characteristic of discharged batteries.  Are you sure 
the 
ET charger is putting out enough voltage to charge them fully?

Assuming that it is, don't junk the batteries yet.  Give them a chance.  
Here's 
something you can try.

Make sure the electrolyte level is above the plates, then give them a full 
charge (charge for 8-12 hours).  Discharge them with a light load, just 
until 
they seem a bit weak.  Charge again.  Repeat this a dozen or more times 
(unused batteries lose capacity and need to be "exercised").

Then, give them a long, slow equalization charge.  The ET charger is a bit 
brutal for this purpose, but if you don't have anything else it will have 
to do.  
Keep them bubbling gently for a day or two, or until the voltage (measured 
carefully and accurately with a digital multimeter while on charge) has 
pretty 
well stopped rising.

Follow this with more cycling as above to exercise them.

This regimen has roughly the same effect as the high-priced "desulfators." 
 If 
the batteries have enough capacity after this to mow the lawn, great.   
Otherwise, it's probably time for new ones.

I have been satisfied with batteries from Trojan and US Battery (also sold 
under the "Interstate Workaholic" brand).  In my experience, difference in 
 
maintenance and use will account for most the difference in life between 
these two brands.  I have been less satisfied with Exide, though some 
people 
do like them.  I have no experience with GNB but haven't heard much good 
about them.

Sam's Club and other generic sources buy from whomever bids lowest, and 
often the bid depends on how close the supplier is to the store or 
warehouse. 
 Thus the Sam's Clubs in California might have different batteries from 
the 
Sam's Clubs in Ohio.  You might get US or Trojan, but you're just as 
likely to 
get somebody else's.

If you're getting quotes over $55, call another dealer.  Check with the 
local 
golf course (or the people who maintain their cars) and ask where they get 
their batteries.  Drop in on them and make friends; they may be able to 
set 
you up with a good price.  Something in the $40-45 range is very good.  
Around $50 is decent.  After my first bunch (I also run on-road EVs), I've 
never paid more than $55 each.

Hand-selected used batteries from a golf car dealer or golf course can be 
a 
good choice for people who don't need the maximum range.  These are 
usually available for $10-20 each.

Hope this helps.

David Roden
Akron OH USA