help.. 12v batter will not charge.. - Kayak Fishing Adventures on Big Water’s Edge

yotasan · 08-24-2012, 07:11 PM

i used my fish finder battery to run a bilge pump to drain a 300 gallon aquarium. i figured it would have enough juice in it but i was wrong.

any ways, i hooked up the bilge pump and lets say we set it and forgot it.. came back to a half filled tank and the pump stopped working.. uh oh, battery is dead.

tried to charge it but the charger beeps low voltage and will not charge. any recommendations? the battery is 12v 10.5 amp.

Ddwineguy · 08-24-2012, 07:36 PM

You probably killed your battery. In reality you should never discharge even a high end AGM more than 60 percent to keep it in optimum condition. A good quality digital charger charging a completely dead battery on a low setting can sometimes revive it, but rarely will you ever get the same amp hours again from that battery.

Poxy Boggards · 08-27-2012, 01:04 PM

Sounds like a toasted battery. I had the same issue, where my old battery would not hold a proper charge. Hooked up a volt meter and found out that even though it was charged to over 12 volts, once under a load it would drop to under 10 volts. Time for a new battery!

addicted2sp33d · 08-27-2012, 01:19 PM

Before you toss/replace the battery, take it to a NAPA or AutoZone. Their industrial (high Volt/Amp) chargers flow a little more juice and can sometimes resuscitate a drained battery.

The NAPA near my house has already saved me from buying a new battery once; after I accidentally drained it completely. I hooked it up to my 120V car battery charger for 24 hours and it was unable to charge the battery, so I was prepared to get a new battery at that point.

The guy at NAPA said, let's give it a few hours on our charger and see what happens. When I got back, the battery was again able to hold a charge and I walked out of there with the battery that's still working today, 2 years later.

RedSledTeam · 08-27-2012, 04:24 PM

Your charger beeps when it senses a voltage that is less than the minimum set at the factory and thus will not charge. Try to charge it with another charger that doesn't have a minimum setting or even try a float charger. If try to "shock" it with a high amperage charger be ready to use a scatter shield or have secondary containment for the hazard materials you are about to detonate! Always try low voltage first; it's much safer.

mtnbykr2 · 08-27-2012, 04:40 PM

speakin' of batteries, sorry for the thread jack, but can anyone tell me what they are getting out of a 9amp hr running an HDS5, mine goes about 8 hours and dumps, anyone have similar results?
As far as the battery not charging, another non digital charger should get the battery going, I have a digital and if I run the batteries down low enough I have to give them a little jolt from another charger, as long as the battery isn't too old it should come back

08-24-2012, 07:11 PM	#1
yotasan Member Join Date: Dec 2008 Location: south orange county Posts: 84	help.. 12v batter will not charge.. i used my fish finder battery to run a bilge pump to drain a 300 gallon aquarium. i figured it would have enough juice in it but i was wrong. any ways, i hooked up the bilge pump and lets say we set it and forgot it.. came back to a half filled tank and the pump stopped working.. uh oh, battery is dead. tried to charge it but the charger beeps low voltage and will not charge. any recommendations? the battery is 12v 10.5 amp. __________________

08-27-2012, 01:19 PM	#4
addicted2sp33d Here fishy fishy fishy... Join Date: May 2011 Location: San Diego, CA Posts: 774	Before you toss/replace the battery, take it to a NAPA or AutoZone. Their industrial (high Volt/Amp) chargers flow a little more juice and can sometimes resuscitate a drained battery. The NAPA near my house has already saved me from buying a new battery once; after I accidentally drained it completely. I hooked it up to my 120V car battery charger for 24 hours and it was unable to charge the battery, so I was prepared to get a new battery at that point. The guy at NAPA said, let's give it a few hours on our charger and see what happens. When I got back, the battery was again able to hold a charge and I walked out of there with the battery that's still working today, 2 years later. Last edited by addicted2sp33d; 08-27-2012 at 01:24 PM.

08-27-2012, 04:40 PM	#6
mtnbykr2 Senior Member Join Date: Sep 2009 Location: newbury park ca Posts: 2,323	speakin' of batteries, sorry for the thread jack, but can anyone tell me what they are getting out of a 9amp hr running an HDS5, mine goes about 8 hours and dumps, anyone have similar results? As far as the battery not charging, another non digital charger should get the battery going, I have a digital and if I run the batteries down low enough I have to give them a little jolt from another charger, as long as the battery isn't too old it should come back __________________

08-24-2012, 07:36 PM	#2
Ddwineguy Senior Member Join Date: Apr 2012 Location: san diego Posts: 210	You probably killed your battery. In reality you should never discharge even a high end AGM more than 60 percent to keep it in optimum condition. A good quality digital charger charging a completely dead battery on a low setting can sometimes revive it, but rarely will you ever get the same amp hours again from that battery.

08-27-2012, 01:04 PM	#3
Poxy Boggards Senior Member Join Date: Jun 2012 Posts: 146	Sounds like a toasted battery. I had the same issue, where my old battery would not hold a proper charge. Hooked up a volt meter and found out that even though it was charged to over 12 volts, once under a load it would drop to under 10 volts. Time for a new battery!

08-27-2012, 04:24 PM	#5
RedSledTeam Daddeo Join Date: Jul 2010 Location: OC Posts: 660	Your charger beeps when it senses a voltage that is less than the minimum set at the factory and thus will not charge. Try to charge it with another charger that doesn't have a minimum setting or even try a float charger. If try to "shock" it with a high amperage charger be ready to use a scatter shield or have secondary containment for the hazard materials you are about to detonate! Always try low voltage first; it's much safer.