[bcrvman]

Originally Posted by whutfles

I am on my 2nd set of AGM batteries and like them. I got to wondering if they needed to be vented? So I googled "Do AGM batteries need to be vented"? I found an article by RV Nerds titled "Electrical Myths, Part 4 AGM Batteries Don't Need Venting" By Dave Nov 1, 2017.

The article explained how they do need to be vented because they can release hydrogen gas in an overcharge situation. Then they quoted numerous organizations and their rules on ventning. One was this:

RVIA
The Recreational Vehicle Industry Association’s Low-Voltage similarly requires venting for all battery locations, whether or not batteries are actually installed, and prohibits installation of other potentially spark-producing equipment in the same compartment (e.g. inverters, charge controllers, disconnect switches):

Now I have read on this Forum many accounts of owners suggesting installing a battery disconnect switch to avoid the arcing when disconnecting a terminal and to avoid the drain when in storage. So I installed a disconnect switch and yes it is in the same compartment as the battery. Is that paragraph above from the RVIA correct and still in effect? And what is the difference in having a disconnect switch in the same compartment or not having one and getting the almost always spark when you connect or reconnect the battery terminal?

Well that's just both hilarious and sad. My old flooded lead acid batteries were within inches of several large breakers for the house circuit and the hydraulics plus all the electrical stuff to operate the hydraulics. Yes the battery box was vented through the floor and to the outside front, but there was still a non zero probability explosive gas could escape. I have since replaced with Lithiuim so don't care but others might want to check closely.