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Old 01-14-2009, 09:22 PM   #1
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Default Charging a 12V gell cell starter box battery

I just got a new 12V gel cell 12v battery for my starter box about 2 months ago. I generally plug it in the night before an event and it's been pretty good the next day. However, the last couple events it's been very weak after a night or more of charging. I have to push the buggy down over and over and only get a little turn out of each flywheel to starter box contact. When the buggy has started and is warm it generally starts up quickly. It's only challenging the first time I start it cold and with no fuel in the system.

I've been told I can charge it with an automotive charger so I borrowed one. The charger I'm using has a 2amp A/C charge and a 10amp D/C charge. Which one, if any, would be the best to use for my 12v battery?
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Old 01-14-2009, 11:50 PM   #2
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I charge my gel cells at 2 amps (obviously a DC charger for auto batteries).. anything more any you're asking for trouble.

I bought a cheap walmart battery charger (17 bucks) and it works like a charm. I think I charge my starter box something like once a month.
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Old 01-15-2009, 07:41 AM   #3
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you could also usa a battery tender charger.. it will keep it topped off all of the time
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Old 01-16-2009, 10:42 PM   #4
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yeah I run 12volts in my boxes, and ive got these little wallchargers, theyre just a little box type the plug in with alligator clips...similar to this one:


only mine are form Hangar12 or whatever the company is called. Never had a problem, plug it in and charge overnight, ready to go in the morning
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Old 01-17-2009, 11:15 AM   #5
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The 2-amp charger would be the best. Your gel cell is probably only a 9 amp battery, so you need to be careful not to overcharge it. I charge my gel cell for 2 hours at 1 amp (=2 amp charge) every other race.

Some things to consider are:
Have you measured the voltage on the gel cell before and after charging?
Have you tried another battery to make sure it is the battery?
How hard is the motor to turn over by hand?
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Old 01-17-2009, 01:29 PM   #6
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Originally Posted by jamminnay View Post
you could also usa a battery tender charger.. it will keep it topped off all of the time
This is what I do with mine - its also called a float type or float style charger. Mine are 7ah batts and when the tender is charging, its 750ma. The Hobbico wall type plug in charger sold as a gel cell charger uses 600ma.

I have a motorcycle batt trickle charger and its 1amp. I have an auto batt trickle charger and its 2amps. Not sure I'd charge at more than 1amp. Gel cells are designed for trickle charging.
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Old 01-17-2009, 05:02 PM   #7
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Have been told by many manufacturers of the sealed lead acid or AGM batteries to charge at no more than 1 amp but 1/10 of rating is recommended. 7 Ah battery would be charged at .7 amps for maximum life of the battery. You have to remember that these batteries are sealed and have no way of properly venting gas when charging at higher rates is what I have been told.
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Old 01-17-2009, 05:54 PM   #8
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I use a Schumacher Speed Charge computer smart charger that has 3 different battery setting: regular 12v, deep cycle 12v and AMG or gell cell
with 3 different charge rates, 2A, 12A, 25A, the computer fluctuates the power into the gell cells by regulating the voltage of the pack so it dont over charge the battery and overheat the cell. I have used this charger on 3 different bump boxes last year and all of them act just like brand new.
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Old 01-17-2009, 07:17 PM   #9
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Have you checked all of the connectors and the contact
switch parts in your starter box. The contact parts get
fried after a bit of use. I wire all my boxes useing a 30 amp
relay, to keep the switches and contacts from frying. Also,
replace any connectors that you can with some good Deans
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