In the North East, we frequently store our equipment over the winter months. During that time, the associated batteries can take a beating. If they are left unattended and the voltage drops, the electrolytes can freeze and the battery is ruined. If the battery is over charged, the electrolyte boils, the plates warp and the battery is rendered useless. With the cost of a good battery being substantial, a proper maintenance plan is cost effective.

Many of the new LQs have multiple stage converters, that do an excellent job of charging and maintaining their batteries. However to utilise these features, the entire electrical system has to be energised. Electrical components are rated on MTBF. (mean time between failures) The various components have an average service life before they fail. The converter and other electrical components that are energised whenever the trailer's electrical system is on, are expensive to replace, and are not all needed just to maintain a battery.

There is a much easier and less expensive way to protect your batteries. A small charger, called a battery float charger, is a stand alone devise that will maintain the proper voltage of the battery (ies). With its low amperage draw, it plugs into any common, inexpensive, smaller AWG extension cord, and doesn't require the 20 or 30 amp shore cord.

The charger clips onto the battery posts or leads, and the trailers circuits are completely shut down. In the Spring, the batteries are found to be fully charged, the electrolite levels are usually maintained, and they did not have to be removed from the trailer. Their longevity has been greatly enhanced.

Several years ago I bought two of these:

http://www.batterymart.com/p-battery-tender-jr-12v-0_75a-battery-charger.html?utm_source=GoogleBase&utm_medium=CPC&gclid=CJTK9qLmv7MCFYuZ4AodmTMAxw

They have worked very well and simplified my winter maintenance.

Three years ago, I bought several of these:

http://www.harborfreight.com/automotive-motorcycle/battery/automatic-battery-float-charger-42292.html

Each of them has worked equally as well, at a greatly reduced price. Presently they are on sale for $4.95, (coupon # 96698369) item lot # 42292/69594/69955

They certainly make life a little easier

If you have two 12V batteries in parallel, one float charger will maintain them both.

If you keep your fridge on all winter using a shore cord, you will not need an external battery charger. The converter will keep the batteries charged. Since you have experienced a good service life from them, your converter is working very well.