Hybrid Car – More Fun with Less Gas

Champion 3000 Watt Generator, Hard Starting when Cold - Page 9

register ::  Login Password  :: Lost Password?
Posted by ads on January 5, 2019, 4:05 am
On Fri, 4 Jan 2019 12:41:49 -0500, "Jim Wilkins"

I've been researching alternative batteries for the eventuality that
the current battery bank must be replaced.  There is semi-local
(reasonable driving distance) vendor who has new Interstate Powercare
batteries (12MQ2400, 12 volt, 94AH [8 hour]) for $5 each (exchange).
I need to ask if he needs the exact battery or just a "core" of
similar weight.  $90 to replace the entire battery bank would be a
very good price.

The single cell failure seems to be a common failure mode for small
VRLA batteries.  I have several that died "in one cell" by the voltage

I've yet to try the "recover your AGM battery" process of opening the
battery up and adding water to the low cell.  While I can see that it
might work in the short term, whatever caused that cell to fail is
still there and I'd expect it to fail again in the not-too-distant

I've been spending the recent rainy days (4 days rain, 1 day not rain,
repeat) catching up on my fiction writing.  I published my first
TEOTWAWKI novel a little over two years ago and have sold some 1700
copies.  Probably OK for an unknown author's first book:

I'll have two more books with a similar family theme on Amazon by the
end of this month.

This email has been checked for viruses by Avast antivirus software.

Posted by Jim Wilkins on January 5, 2019, 2:01 pm
<ads> wrote in message  

Adding water didn't improve the one weak 12V,18A AGM I tried it on.  
The valve caps were soft rubber and easy to remove.

My discharge test loads are an assortment of large rotary rheostats,  
up to 1 Ohm 1000W (31A). Their advantage is a steady current that  
doesn't confuse the ammeter with switching noise, the disadvantage is  
that the intended constant current or power ramps down between  
unevenly timed readjustments. Successive capacity measurements can  
vary around +/- 10%, possibly due to this procedure, which obscures  
small changes.

A DC-AC inverter makes a pretty good constant-power load with a  
built-in but non adjustable low voltage cutoff. My crock pot draws  
100W from the inverter without becoming dangerously hot, while the  
rheostats approach 600F at their rated power. An inverter does produce  
switching noise that seems to randomize the low voltage trip point.

The run time of an AC-powered refrigerator is hard to estimate because  
the inverter will trip out on a starting surge voltage drop although  
the battery could still provide the running current. My datalogger  
uses PC-linked multimeters which can't sample faster than once per  
second, and miss spikes. The DC Alpicool's ramped soft start is a help  


Posted by Jim Wilkins on January 5, 2019, 2:15 pm
 <ads> wrote in message  

So you live fairly close to "Neon" John DeArmond in Tellico Plains.

Posted by ads on January 6, 2019, 1:43 am
 On Sat, 5 Jan 2019 09:15:23 -0500, "Jim Wilkins"

Not close, but almost due south - about 3 hours by road.

This email has been checked for viruses by Avast antivirus software.

Posted by Jim Wilkins on January 21, 2019, 3:56 pm
What does your commercial battery tester measure?

My experience is with industrial battery testers designed in-house,  
mostly for Lithiums. They performed a time-consuming full discharge  
and recharge cycle that recalibrates the battery pack's internal fuel  
gauge. I haven't seen convincing evidence that the quicker DC or AC  
impedance testers for lead-acids correlate well with remaining  
capacity or service life.

This Thread
Bookmark this thread:
  • Subject
  • Author
  • Date
please rate this thread