How Long Can A 80Ah Battery Last?

TLDR: 

A 80Ah lithium battery would last 1-2 days off-grid with typical use, i.e. LED lights, phone charging, fridge running on gas. This assumes minimal charge is inputted to the battery via solar panels, mains hook up or engine charging.

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It is extremely difficult to estimate how long a battery will last between charges, as everyone's energy use is different, has different equipment, off-grid demands, charging abilities, and more. We can give you an accurate estimation, but you'll need to contact us and let us know what equipment you have and the length of time you wish to be off-grid.

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However, for each of our 12V batteries, we do have a generalised period of time they can perform with no charge input, based on a typical caravan/motorhome. It's worth noting that as soon as you start moving, the vehicle will charge the leisure battery, so if you move from place to place, you'll be inputting some charge. Likewise for solar charging; it all depends on the UV levels on the day and what size panel you have. For our recommendations, we make it simple and base our estimates on no charging whatsoever; if you have a solar panel or will travel with the vehicle, the estimates we give will be underestimated.

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For a typical motorhome/caravan, we estimate around 1,500Wh (1.5kWh) would be demanded from the battery in a typical day:

• 80W for a 12V fridge - running for 12 hours (turning off and on throughout the day) = 960Wh
• 50W for a water pump - running for 1 hour = 50Wh
• 15W for LED lights - running for 5 hours = 75Wh
• 80W for device charging (phone, laptop etc) - running for 2 hours = 160Wh
• 85W for a 12V TV - running for 3 hours = 255Wh
• With 12V Fridge Total = 1,500Wh per day
• With Fridge On Gas Total = 540Wh per day

Our 80Ah battery that has 1,024Wh of capacity, would last ~16 hours with no charge input and the fridge running from battery power.

If you are able to run your fridge on gas, the discharge time shoots up to about 45 hours.

If you have solar panels and/or will move sites, the discharge time will increase.

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Our 80Ah lithium battery is designed for those who want a drop-in replacement to their existing 100-120Ah lead acid battery to get the benefit of faster charging and longer lifespan, but do not need a massive increase in capacity (and wishes to avoid the increased cost of larger capacity batteries). Perfect for the leisurely weekend camper.

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Should you have other devices, like non-12V TV's, less efficient fridges that cannot be run on gas, heaters, inverters and more, or you want to go off-grid for longer than a day or so, we recommend going for a larger capacity battery.

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We always recommend building in a extra capacity buffer when sizing up your next battery; just in case you get overcast days, stuck somewhere without mains hookups, potential for adding extras down the line, and it gives the battery a little easier life not having to go from 100% to 0% with each use.