I have had an AGM 120 Ah battery as an Auxiliary battery for a while, running the 40 litre Waeco and the tyre compressor on trips. I take it out when I do not need it as it is in a plastic battery box.
I thought there must be a better solution than a lead based battery.
I got a 125 Ah Lithium battery from Sentry.
As a comparison:
Weight:
AGM 38 kg
Lithium 15 kg
Size:
Comparable, the Lithium is slightly smaller, but only slightly. It fits easily in the same battery box with a little room to spare.
Usable Capacity:
AGM 60 Ah, 12.2 Volts 50% SOC, significantly less under load
Lithium 100 Ah 12.8 Volts at 80% SOC, regardless of load
Expected Life:
AGM Maybe 8 years, looked after carefully
Lithium Over 20 years expected
The Lithium battery has a Bluetooth setup which allows me to monitor Voltage, SOC, temperature, charging rate, discharging rate, etc. on my phone.
So, 40% the weight, 65% more useable capacity, over twice the life expectancy AND it maintains a constant, useful Voltage right down to at least 20% SOC. It is so much easier to get in and out of the car and has given me back 23 kg of payload.
I am charging it with a Ctek D250S Dual DC-DC and Solar Controller, as per the suppliers instructions - the exact same one I was using for the AGM.
I'm a happy camper!
Cheers
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