safe to use sealed batteries in coach?

rich85704 wrote:
In response to some: what's the difference between a sealed flooded battery and an AGM battery? Are sealed batteries not really sealed?

R

Books are written on the differences between the Flooded Wet cell and AGM batteries. When you read forums, there is lots of misinformation on both. I will offer a short version which may generate more questions.

Flooded Wet cell batteries are the most common found in cars, and much cheaper to build than AGM batteries. Flooded Wet cell batteries are made up of plates which are suspended in acid (liquid). The liquid must cover the plates. When the battery is charged, its normal charging results in some of the liquid turning to gas. Typically this gas is contained inside the battery and turned back to a liquid. The reason we have to add water periodically is because the gas has escaped from the battery. This gas can make you sick or kill you. In my opinion, a sealed Flooded Wet cell battery in theory at least allows less gas to escape.

AGM (Absorbent Glass Mat) is often confused with Gel batteries. This is from the following link Battery University:
The sulfuric acid is absorbed by a very fine fiberglass mat, making the battery spill-proof. This enables shipment without hazardous material restrictions. The plates can be made flat to resemble a standard flooded lead acid pack in a rectangular case; they can also be wound into a cylindrical cell.


I personally have had flooded wet cell batteries in RVs since the mid70s and everyone fail due to my lack of maintenance. The AGM requires no maintenance. AGMs tolerate cold much better than Flooded Wet cell with the added benefit I can use it inside the RV where I have better temp control. My friends and I have used Lifeline and Universal brand AGMs with no complaints. We no longer have to mess with adding water to our batteries and can leave them in storage disconnected for several months and they will be fully charged.

Wayne

2oldman wrote:
Get Lithium. big money, big convenience and safety.

Unless one shorts out and catches fire !!
Or does that happen only with phones and games ??

rich85704 wrote:
Are sealed batteries not really sealed?

Yes they are sealed......under normal conditions......but things like physical damage in an accident or a HUGE charging voltage overload can cause them to become un-sealed.

rich85704 wrote:
In response to some: what's the difference between a sealed flooded battery and an AGM battery? Are sealed batteries not really sealed?

R

If it has liquid inside it there must be some sort of vent, period.

The 'sealed' ones don't vent at the battery cap, there is a case vent which connects to a tube (usually provided with each battery) to vent the battery to a safe location. A lot of European vehicles have the battery located in the trunk or under the rear seat. In cases like that the battery has a tube which goes through the body to the underside for venting or overflow.

If properly done with an external vent tube I don't see any problem with putting a battery on the inside.

Get Lithium. big money, big convenience and safety.

I would not even consider wet cell batteries inside. When they say sealed, it does not mean literally. It is very common to see corrosion around the post of a wet cell battery. That corrosion is a result of a leaking battery. The posts is not the only place it can leak, and you can see that the posts are sealed. This is usually from outgassing during the charging process.

AGM batteries are designed differently, and cannot leak. This is why they can be mounted in any position and can be shipped. On extremely rare charging conditions, they can outgas. Contrary to popular belief, the do not need special chargers.

I have been using AGM batteries in my camper since 2005. It is mounted inside my camper. I can provide you a list of advantages for using the AGM batteries.

Wayne

In response to some: what's the difference between a sealed flooded battery and an AGM battery? Are sealed batteries not really sealed?

R

AGM batteries, yes.

Sealed (or unsealed) flooded batteries, not so much without battery cases sealed from the inside (and vented to the outside). This may not be too hard to achieve depending on your setup, truthfully.

If money is no object, you may wish to investigate lithium batteries.

If your Santara is set up like my '98 Santara, you can get a pair of golf cart batteries in the tray under the steps if you modify it to hold the batteries lower (giving more height clearance), which would give you about 220 Ah capacity without giving up any inside space. I posted something about how I did this awhile ago, but I can't find it with a quick search now...basically cutting the lower angle iron tray off and bolting on one made from deeper angle iron and fabricating some wooden blocks to keep the batteries in position. I use nylon tie-down straps from Harbor Freight to secure the batteries. It's worked out very well so far.

I would not place a wet cell battery in the living area of my RV without some ability to vent the battery to the outside - my concern would be gassing during the charging. Not that hard to vent - build/buy a container to hold he batteries and attach a hose which leads to outside (any RV outlet will have the outside hose trim piece). Don't have any experience with AGM's - might be different. Just my O2.

We have sealed AGM batteries in our rig. Many who own the same type of rig expand their battery capacity, by placing the additional bats. adjacent to the standard bats.(outside compartment) which happens to be inside, under the fridge. No problems reported with this set-up.