Ok, you have reached the moment when you need to decide on which battery(s) to buy for your TT. So many to choose from..... How do you handle the "Process of Elimination"? Size? Weight? Ah?
SIZE:
Well SIZE could eliminate a lot of choices and restrict the batteries output. Weight is proportionate to the amount of lead which will determine the batteries performance. Probably not the best method to use in a comparison.
AMP HOUR RATINGS: (probably the most common)
I think we are getting warmer at which is the best method to be used for battery comparison. Ah, usually printed right on the battery case. Big numbers! But all Ah ratings printed on batteries are not "EQUAL". Manufacturers tend to use different discharge rates. Some use 10Hr, some use 20Hr and of course the 100Hr rate. You can only find out which they used by looking up the battery specifications on the manufacturers web site.
RUN TIME RATINGS:
(Best method for selecting a deep cycle battery) This is probably the best method and the least used for comparing 2 deep cycle batteries. It levels the playing field. It eliminates the hassle of trying to figure out which discharge rate the battery manufacturers used, or is the new technology used in the battery worth it, it all boils down to how long that Tv will run in the TT, or if it has enough power to keep the CPAP machine running all night.. How long will the TT's heating system last. So, what does a "Runtime Rating" give you? It will show you how many minutes that battery will provide power (between 12.6 volts and 10.5volts) while a constant load is applied. The loads advertised are usually 25Amps and 75Amps. It is best to use the 25Amp load results as it is the closest to the actual loads in a TT. This method is only for comparison and NOT FOR ACTUAL MINUTES that you will have. Why, as mentioned... the 25Amp load was applied to the battery and the test stopped when the battery got to 10.5VDC (a dead battery). To keep your battery for a long time you can only use 50% of those minutes, which will put your battery voltage at about 12.0VDC. So if the battery (Trojan T-105) is rated at 447 minutes, you only have 223 minutes or 3.7 hours of 25 amp load use. Will that be long enough or do you need to double the number of batteries??????
I hope this helps a little when the time comes and you need to select that next battery(s) and make sure it will provide enough power for your camping lifestyle. Below is an example of Trojan Batteries specifications.
Don
My Registry
RVing with SOLAR
Linear Mode
