Tech Question What is the difference between Automotive and Deep Cycle batteries?

To the best of my knowledge and experience the fluid should be clear, like water. The liquid is dilute sulphuric acid just as any lead-acid battery contains.
The deep cycle battery differs not in the electrolyte but in the construction, using different separators, thicker plates and deeper sediment trays.

If the fluid is discoloured (varying from light grey to black) it is likely to indicate a charge rate that is too high, over charging or physical vibration has disturbed sediment from the trays or from the plates or perhaps the battery has been tilted. Sometimes lightly discoloured fluid is of little detriment and will settle in time if left undisturbed. Sometimes it is a sign of a failing battery. Certainly it would be wise to check the charging system for the correct operation.

Above all, buy the best battery you can afford. You can't have too much battery! A standard sealed lead-acid battery is okay for the engine, but I would suggest an AGM battery for the coach. AGMs are longer lasting, charge quicker and can stand abuse. Make sure it is a deep cycle battery for a RV, NOT A MARINE TYPE DEEP CYCLE. Marine type deep-cycle batteries are designed to start engines along with their deep-cycle capabilities. They WILL NOT last in an RV.

Make sure the replacement is the same design i.e. + post on left (or whichever). Compare to original battery. Switch breaker off for coach. Replace battery. Hook up the RED cable to + FIRST, then black cable to ground. Switch power back on. You can charge it if you want to, but I never noticed any need.

Deep cycle is typically for long duration loads like lights or a troling motor but not very high starting currents. Unless marked, an RV battery is a combination starting running battery. It may have a higher starting current than the deep cycle, but not as long of a run time.

Battery Voltage is usually always 12, Amperage can vary slightly with no major problems. 35 Amp is standard and will not present any problems.

Lights and slide are 12 volts ... check your battery ... and your battery charger ... DO NOT TRY TO OPERATE your trailer on a dead or battery-less unit. You need a good battery for things to work properly ... deep cycle not automotive.

Good luck with our repair.

Take the batteries to a battery shop or a Battery plus store have them load test the batteries. Deep cycle batteries are different from normal batteries. Normal batteries are design for max output for short periods of time, Deep cycle batteries are designed for a modest output for long periods of time. My batteries are rated at 35 amp/hr.. Basically a load tester places a load in amps [cranking amps] on the battery. How many cranking amps depends on if there is a voltage drop when you apply the load. I can apply 480 cranking amps before my voltage drops. What i do is load test a new battery of the same type to find out the cranking amps. You will not find a cranking amp rating for aq deep cycle battery but retail places have load testers that read in cranking amps. Use only deep cycle batteries in scooters, garden tracker batteries will not last. If the batteries are ok test the charger. A CHARGER KNOWS THE CHARGE OF THE BATTERY BY BATTERY RESISTANCE. As a battery charges its resistance get bigger. Once the battery reaches a preset resistance the light goes solid. You can have the charger checked by a battery shop. To properly charge a battery a charger will put out 27volts @ 4amps, they can easily test for voltage. Now if the charger is built in there is going to be an external fuse find it, check it. hope this helps

Automotive batteries are designed for a quick draw of amperage (when starting) and then get constantly recharged using the alternator when driving. If you are using an auto battery for inversion, it will drain much quicker. Depending on how/where you are using it, you could charge the battery when a meter shows a voltage drop. Better recommendation would be to use a marine battery, which is a deep cycle battery. Deep cycle batteries last much longer between charges, as they are designed to have a constant draw (trolling motors, etc.).

Hi, the deep cycle battery is for the home part and should charge through the external connector port. The regular battery is for the engine. Is the regular battery charged up too?

The really only way one can tell if batteries are being charged is assure them are topped off then trickle charge them with external charger overnight and then check the voltage is 13-14.5 VDC. If not check that battery life is not expired and exchange them if it is. ALSO... one can always extend the life of batteries (deep-cycle) by charging them with a large professional automotive unit in the high power START position over night. WARNING: Assure the caps are loose as you "boil away" the plate corrosion over night due to the very explosive H2 gas generated. No smoking!!