inverter battery

[northwoodman]

I have a battery for my inverter installed separately from my house battery from the dealership. I was going in installed them in parallel, so that both batteries can be charged though the converter or truck. My question is when I attached the house ground to the inverter battery I got a connection that sparked, even though the inverter was off. I thought that if the inverter was off I would not have a connection would not get a spark. Can anyone give me an explanation before I continue. Thanks

[craigav]

Even if yours isn't a Lithium battery, the same concepts apply as in this video. What you experienced is not all that uncommon. ~CA

https://www.youtube.com/watch?v=ZlrtmJRfSP8