There are two uses for batteries, long-distance buses and household batteries. The coach battery is the battery used to start the RV. These are ordinary 12 V car or truck batteries designed to provide large amounts of current in a short period of time. Household batteries are deep cycle batteries designed to provide lower current for longer periods of time.
Most of us will understand the coach car batteries and can tell when to replace them. They will last 3-5 years. You can tell when the coach's battery has started to deteriorate because of difficulty starting the lights, starting the engine, turning the crank slowly or dying quickly. Maintenance and inspection will be described below.
Just because of the wide range of uses and types, household batteries are difficult to cover. Let's start with purpose. Household batteries are designed to operate all equipment in the equipment, from lights to fans and heaters. Almost everything in motorhomes is battery powered. Therefore, these need to provide current (amperage) for a long time. Usually, the house battery can be called to provide current for several days at low current. This type of battery is called a deep cycle battery. All RVs are running on 12 v DC systems. However, not all RVs use 12 V batteries. Many car houses will use 6 volt batteries. 6 volt batteries are often referred to as golf cart batteries because this is their main purpose.
There are too many battery types here. Basically, the more expensive the battery, the longer the service life. Maintenance-free batteries only mean that you do not need to add water during maintenance.

When it comes to maintenance, what maintenance should be performed and when. If the battery is used once a day or weekly, most maintenance work needs to be kept clean and charged. If your battery is only used to provide limited current, you can use a current charger to keep it charged. The ckle flow charger can be AC ​​(household current) or solar energy. They provide a small amount of current to keep the battery fully charged.
If the battery is a battery with a removable cover (ie IE maintenance type battery), then you will need more maintenance from time to time. Hydrometers are required for maintenance-free batteries. The hydrometer is used to check the specific gravity of the battery (acid to water). Its purpose is to determine whether it is necessary to add distilled water or battery acid to the battery. All you need to do is remove the cover of each battery and draw a little liquid into the hydrometer. It will tell you the state of the fluid. Most of the time, you will need to add distilled water. Add a little at a time and retest.
If you plan to store the RV for a period of time, remove the battery, place it in a cool (non-cold or hot) place, and then place a stream charger on it. This will allow the battery to be fully charged and ready for use. Make sure to check that the maintenance-free battery is correct about once a month.
Finally, when not in use and not connected to any type of charger, a fully charged battery reading should be greater than 13.2 volts. If the voltage drops below 13 volts, the life of the battery will be exhausted and the battery should be replaced.

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