Battery Fail

[Bduck]

As I was rummaging around in the garage looking to work a project, noticed a very noticeable odor of sulfur. Walking by my boat I usually check the onboard charger for the green lights. Number 1 was solid red & number 2 was flashing yellow. So I unplugged the charger which maintained an AGM on #1 and a wet cell on #2. I would get around to troubleshooting a little later after I get a couple of things done. 2hrs later I noticed the sulfur odor was getting stronger as I walked thru the garage, thankfully a breeze was blowing to air out the garage. My immediate attention now is drawn to the boat batteries, when opening battery compartment panel, I could hear the wet cell boiling. The AGM was supplying power to it continuing the boil. I then shutdown batt switch to off and disconnected the wet cell batt finding this batt was too hot to physically to touch. Once I got it removed, I took an infrared digital temperature reader finding batt temp was 171°F. This had disaster written all over it if it had gone any further sitting in the boat. This was an Interstate Costco battery I bought 6yrs ago and replaced with another AGM. This is my last AGM upgrade I was awaiting to do but not at the expense of a battery meltdown. My diesel truck takes 2 AGM's, Caddy Escalade & Buick took 1ea. I was sold long ago on AGM with final upgrade made, $$$$'s but well worth it.

[wiperhunter2]

As I was rummaging around in the garage looking to work a project, noticed a very noticeable odor of sulfur. Walking by my boat I usually check the onboard charger for the green lights. Number 1 was solid red & number 2 was flashing yellow. So I unplugged the charger which maintained an AGM on #1 and a wet cell on #2. I would get around to troubleshooting a little later after I get a couple of things done. 2hrs later I noticed the sulfur odor was getting stronger as I walked thru the garage, thankfully a breeze was blowing to air out the garage. My immediate attention now is drawn to the boat batteries, when opening battery compartment panel, I could hear the wet cell boiling. The AGM was supplying power to it continuing the boil. I then shutdown batt switch to off and disconnected the wet cell batt finding this batt was too hot to physically to touch. Once I got it removed, I took an infrared digital temperature reader finding batt temp was 171°F. This had disaster written all over it if it had gone any further sitting in the boat. This was an Interstate Costco battery I bought 6yrs ago and replaced with another AGM. This is my last AGM upgrade I was awaiting to do but not at the expense of a battery meltdown. My diesel truck takes 2 AGM's, Caddy Escalade & Buick took 1ea. I was sold long ago on AGM with final upgrade made, $$$$'s but well worth it.

Wow, that sounds scarry, just thinking about what could have happened if you did not catch it when you did. Do you think it could have exploded? Just curious, I know many folks leave their battery plugged in, to maintain their batteries when not in use but I've always been afraid of this happening, so I only keep mine plugged in until it is charged, then I unplug it and the day before I'm planning on taking the boat out again, I plug it in to make sure they a topped off.

[dubob]

I have 2 AGMs powering my Minn Kota and they are on charge almost all the time with the Minn Kota charger mounted in the boat.  Both cranking batteries in my boat are wet cell and are never charged except during the winter when I have them on battery tenders.  My crank batteries have never gone dead.

I have never experienced that which you posted Roger.  Switching to AGMs is a good thing; but you already know that.  

[Bduck]

I've always heard about the nightmares caused with wet cell, never before have experience it up until now and feel lucky catching when I did what could have been disastrous. Even had some really good success with longevity. I feel the quality of wet cell has slid down hill. My onboard battery charger is a 2 bank NOCO therefore I always leave it plugged in. Also, in my 3 vehicles I use a NOCO single smart charger for the AGM's which each I can select type of battery maintaining. I use them when need, especially during cold weather.

Amazon.com: NOCO GENIUS2, 2A Smart Car Battery Charger, 6V and 12V Automotive Charger, Battery Maintainer, Trickle Charger, Float Charger and Desulfator for Motorcycle, ATV, Lithium and Deep Cycle Batteries : Automotive

[LundLefty]

Old skool wet cell batteries can be a PITA, even with proper care and feeding.  I just went to deep-cycle lithium batteries for my bow-mount MinnKota trolling motor and couldn't be happier.  Seriously, the power output lasts "forever".  I can troll for 5-6 hours - our maximum attention span for trolling - and the battery meter on the MK still reads 100%.  We're usually tooling around at 1.0 - 1.5mph, but with the new batteries, and I added a 3-blade TM prop, we can push it to 3.3. Never fish that fast, but was interested in top-end trolling speed.