# Generac 18kw battery exploded this morning...



## skid2964 (Apr 30, 2016)

When my Generac 18KW generator tried to start this morning for it's weekly exercise, the battery exploded with a loud boom. I thought, OK replace battery, glad the generator is OK but should I assume this? I noticed once I removed all the battery pieces and acid that there was voltage from the positive terminal to ground. I assume this was a capacitor in the system that still had a charge? It went away after a while that makes me think this but I wanted to make sure... I don't want to ruin a new battery if there is a problem.


----------



## rhenning (Jul 23, 2011)

I would be calling Generac on Monday morning and asking this same question. They would have the right answer. Roger


----------



## exmar (Jun 29, 2015)

Not an expert on gensets, but the only time I've seen batteries "explode" was due to a direct high current short across the terminals or a charging fault condition, again, putting a high current into the battery. Both these scenarios result in excessive gassing which would explode the case. Again, not a genset expert, just what I've observed on farm equipment, etc.

I would not replace the battery until Generac or a qualified tech could determine what is wrong.


----------



## aandpdan (Oct 8, 2012)

There should be a trickle charger on the battery. That's likely why you saw voltage from the positive to ground.

Could be a number of things including defective battery or charger.

Call your dealer.


----------



## Osviur (Sep 7, 2015)

*Battery explosion*

Hi skid2964,

As exmar says, a direct short across the terminals, or near the starter, where the cables have a thick section, may permit to circulate a very high current, enough to produce heat and explosive gasses that will ignite and explode, destroying the battery.

Another possibility, is the presence of gasses ( Oxig. & Hydrog.), product of a charging process, especially if the battery is not a sealed, gel type battery. These gasses mixed are explosives and a very little spark, may be a weak contact in the terminals, can ignite them and produce the explosion, just starting the generator.

A short circuit current will damage the conductor carrying the abnormal current, at least will melt the insulation, if not the cable itself, dropping the voltage near to zero, discharging any capacitor in the circuit. It is easy to see the damages caused for a short circuit overcurrent.

In the other condition, a gas explosion, there are not burnt cables and the full voltage will remain in the battery, if the 6 cells remain connected with the bridges, and in any capacitor connected in parallel to the power circuit, possibly in the charging circuit. 

Regards.


----------



## EricaRonnie16 (May 12, 2016)

Generic 18kw battery package you label is a ruthless one to acquire on. I disrespectfully advise that you get in individual instruction from nobody who has prepared such and connect already. 
____________________

https://qualitygeneratorsonline.wordpress.com/2016/05/09/generac-guardian-generators-offer-better-value-for-money/


----------



## Dan N. (Jul 23, 2015)

Depending on the year of the generator......... If it is the square box kind, they were known to blow batteries up due to overcharging. This seems to have been eliminated when they came out with the Nexus controller style. Your saying 18KW and I'm assuming that is a 20KW on propane?


----------



## GeneracGenerator (Nov 24, 2017)

I worked on an older 12 kw Generac generator that just exploded a Duralast battery. Did anyone find a solution to this problem? Here is a quick 21 second video that shows the carnage:


----------



## KRE (Nov 29, 2011)

The issue with generc's blowing battery's is do to their battery chargers, has been for 20+ years. When you buy a price point gen-set you have to understand how they can sell that much kw for that price, compared to quality set manufactures. Box stores are a very poor place to buy or get generator information. Also don't believe all the hype of a TV ad. 
Buy quality, an be done with it.


----------



## jkingrph (Sep 18, 2017)

Get someone who knows what they are doing to check it, otherwise if you put a new battery in it may go boom also. I had that on a fairly new Plymouth car, about 35 years ago, hit the ignition switch and boom and what I thought was smoke, but was mostly electrolyte spray came out of the front. I have no idea what caused it, as I had to be at work and had someone pick me up, and a local service station/garage retrived the car and fixed it. Got it home and washed and washed under the hood and kept the car another 7-8 years with no problems.


----------

