Trojan T-105 versus T-1275

[pauldub]

I'm considering using a pair of T-1275 instead of T-105 to gain some additional amp-hour capacity. Should I expect either of these choices to last for about the same number of 50% discharge/charge cycles? Also, it seems that a pair the 12v in parallel with have less internal resistance that a pair of 6v in series. I'm guessing the pair of 12v would do better running an inverter with a 1000 watt load.

[Roadtripp]

I don't really know about the internal resistance. Is t it the same number,6, of cells? But have heard many times that bang for the buck that 6 volt is the way to go. The golf cart industry uses 6 volt primarily.

[vsheetz]

The manufacturer will have discharge depth/cycles charts on their web site where you can compare the two batteries.

[pauldub]

Originally Posted by vsheetz

The manufacturer will have discharge depth/cycles charts on their web site where you can compare the two batteries.

I didn't find it buy maybe I didn't look hard enough.

[vito.a]

My guess is you will get roughly half the life out of the T-1275 vs the T-105. T-105 batteries are designed for golf carts where they are contantly charged-discharged. The plates and even the case are much thicker.
There is another thread on this forum about T-105 vs T-145. They are higher capacity but taller so make sure you take careful measurements.

[twinboat]

T 1275 are also Golf Car batteries. The service life will be the same as any flooded Trojan battery.

They all give about 1000 cycles to 50% SOC or 500 cycles to 20% SOC. ( State of Charge ).

A pair, in series, of T 105s will give you 225 AH of capacity @ 12 volts. Cost about $280 for the pair.

A pair, in parallel, of T 1275s will give you 300 AH of capacity @ 12 volts. Cost about $480 for the pair.

If you need the capacity, don't have the room for 4 batteries, and don't mind the price, the T 1275 is the way to go.