Recommendations for Battery Tenders

Brett Dikeman brett at
Tue Jul 26 09:00:50 EDT 2005

On Jul 26, 2005, at 6:55 AM, Kneale Brownson wrote:

> Battery Tender IS the name you want.  That's what I use for the  
> eight-volt
> battery in my '37 Graham.  However, why should you need one?  A good
> battery should be able to sit unused for quite a while if the car's
> electrics are in good shape.

"A battery stored at 95° F (35° C) will self-discharge twice as fast  
than one stored at 75° F (23.9° C)."

Also, in summer heat, alternators can put out less if thermally  
regulated, and there's more demand on them from radiator fans  
(especially type 44s), so battery state of charge can be much lower  
in the summer.

Battery Tender is not actually manufactured by the company someone  
else sent a URL for; they're re-labelled by Deltran, the owner of the  
"Battery Tender" trademark.  I don't have the name handy, but there's  
a company that makes OEM units used by Battery Tender, Yuasa, and a  
few others.

Best source is usually a motorcycle and/or ATV dealer.  The wall-wart  
units (usually 500mA) are okay for a perfectly charged car battery  
with no parasitic load, but I'd recommend the 1.5A unit for a car  
battery, since it brings the battery to a full charge (in a  
reasonable amount of time) and has enough capacity to handle battery  
self-discharge on even the heaviest parasitic loads. You typically  
get permanent-hookup, fused leads (w/quick disconnect connector) as a  
side bonus as well.

Griots is a silly waste of money all around, not just on battery  
chargers- I believe they were selling the Porter-Cable RO buffer at  
almost 100% markup OVER what a tool store was selling them for, plus  
they were not including the second counterweight and sanding pad.

"They that give up essential liberty to obtain temporary
safety deserve neither liberty nor safety." - Ben Franklin

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