My leisure battery is 3 years old and needed replacement.
I've bitten the proverbial bullet and purchased a 105 amph FogstarLifePO4 battery on the recommendation of A900. I also purchased a 20amp lithium charger from them as well. I fitted it into my van this week.
Reprogramming my Sterling b2b charger from 60 amp to 30 amp took me a couple of hours with Ben Sterling's help from Sterling.
Interestingly, these battery 2 battery chargers are rated at input to the charger rather than output. So my BB1260 has an input amperage of 60 amps but around 50 amps output amperage. That's apparently fine for charging a 105 amp lithium battery, but Fogstar recommend charging at 20 to 30 amps, as it is kinder to the battery. The battery arrived at 50% charge, and my new 20amp charger fully charged it at 16 amps dropping to 10 amps.
I see my battery charges at around 25 amps when starting the engine, but quickly drops back to 12 amps with a 95% fully charged battery. This is double the charge that the lead acid batteries I had before would accept with a similar charge capacity. But I will still have to bench charge this battery when I use the diesel heater, as short trips won't be enough to full recharge it.
What I love is that even under load, the battery voltage stays at a constant 13.1v.
Incorporated into the battery are heating elements. If the temperature is below freezing, the charge current is diverted to these heating coils by the BMS. Once the battery has warmed up, charging will start.
Sterling's battery with heating coils is twice the price.
Anyway, it's early days and I have a lot to master and experience with this new technology.