Group 24 vs. 27 battery
I'm afraid the battery on my tt has given up the ghost. It won't hold a charge for more than a couple of days with no known draw on it. It is a Group 24 size. My tt is a 2011 model and I assume it i...
Forum Discussion
Only drawbacks of a larger size are greater cost, more weight. The gain is mre capacity, if you use it. Larger size doesn't have longer life, unless your use has been overstressing the smaller one. If you need more capacity, go for it. If you don't, then not. 24 to 27 is about a 50% gain, depending on manufacturer and battery technology.
It is a lot like "do I need a bigger gas tank?" Doesn't matter so much if tank is 100 gallons, 50 gallons, 30 gallons if refueling points are 4-10 gallons apart or your bladdef can hold only 12 (or 6, in the case of my subcompact car) gallons worth of driving time.
Back to batteries, Interstate sells a number of different group 24 batteries, for different applications, and lot of those finding their way into RVs are a dual-purpose marine starting-trolling battery, because that one is pretty cheap to make. They have others that are pure starting, and some models closer to being a slow discharge, deep cycle battery, but none that are like a golf cart battery or even a deep cycle Trojan. Interstate is a brand for marketing, buying from different suppliers for different products. How long it should last would depend on just which model you bought, how it has been used, how well taken care of.
I get 3-7 years our of cheap dual purpose batteries (Interstate, Everstart) that are used lightly and maintained with calculated negligence. They serve to keep the refrigerator running during short stops, help the converter run the slideouts, and start the generator. Since my RV is a motorhome, if the batteries go weak I can start the engine and get adequate power for these tasks from the alternator. If I were really using battery power (e.g. boondocking) I would buy the best deep cycle batteries in the largest size I could carry, and take really goo care of them.
So it depends on how you use the battery. If you don't use it, you don't need more than what you have, which is kind of the minimum for a RV: one group 24 deep cycle, or dual purpose if you have to run slideouts.
It is a lot like "do I need a bigger gas tank?" Doesn't matter so much if tank is 100 gallons, 50 gallons, 30 gallons if refueling points are 4-10 gallons apart or your bladdef can hold only 12 (or 6, in the case of my subcompact car) gallons worth of driving time.
Back to batteries, Interstate sells a number of different group 24 batteries, for different applications, and lot of those finding their way into RVs are a dual-purpose marine starting-trolling battery, because that one is pretty cheap to make. They have others that are pure starting, and some models closer to being a slow discharge, deep cycle battery, but none that are like a golf cart battery or even a deep cycle Trojan. Interstate is a brand for marketing, buying from different suppliers for different products. How long it should last would depend on just which model you bought, how it has been used, how well taken care of.
I get 3-7 years our of cheap dual purpose batteries (Interstate, Everstart) that are used lightly and maintained with calculated negligence. They serve to keep the refrigerator running during short stops, help the converter run the slideouts, and start the generator. Since my RV is a motorhome, if the batteries go weak I can start the engine and get adequate power for these tasks from the alternator. If I were really using battery power (e.g. boondocking) I would buy the best deep cycle batteries in the largest size I could carry, and take really goo care of them.
So it depends on how you use the battery. If you don't use it, you don't need more than what you have, which is kind of the minimum for a RV: one group 24 deep cycle, or dual purpose if you have to run slideouts.
