Originally Posted by Lance
I bought a new 4D Lifeline a couple months ago. It took a few weeks wait like that but came when they said. My old Lifeline was an 2008, though it was going bad the last 2 years. Another friend got over 10 years out of his. I see they say on battery to replace every 3-5 years but I'm hoping for another long run. Wonder why some last and some don't? Mine has solar, so stays charged.
Battery life cycle by definition to the manufacturers is usually 80% of original capacity. The get to that number basically using a 50% discharge cycle. So when you add in actual use and environmental factors (most of those numbers are derived in a lab environment) it can give you a wide range.
Lets say are 4D started 200 Ahr capacity
The biggest factor would be your usage model. Take a guy that uses minimal lighting, occasional water pump, and run the refrigerator. Maybe he then gets up and drives or has solar to replace some of that spent energy. His depth of discharge may only 10% or 20 Ahr. This alone would give him longer life, but when you add in that the battery dies by loosing capacity. So given that his average depth of discharge is 20 Ahr he could get by on a battery that was 20% to 30%(40 to 60Ahr) of it's original state.
Now take a heavy hitter, larger fridge, runs an inverter for coffee or microwave use, runs heater overnight. Maybe his usage model is 40% depth of discharge or 80 Ahr. Now after a couple of years, his battery being at 70%. This now puts his 80 Ahr usage at more than 50% of capacity, this greater than 50% depth of discharge even accelerates the death of his battery.
Then we start adding in the appliances. Inverters, can need large amounts of current, this means there is generally a high voltage drop. Seeing as the battery now has a smaller capacity , that means you run into low voltage voltage issue, that you didn't see before.
When I had a new Lifeline 4D I could easily camp for 2 to 2.5 days. This included running the inverter in the morning to make coffee. A couple of years later on the third morning , the inverter would take a low voltage shutdown. And as is continued to age, that would become on the second morning.
The suburban furnace was another one that would fail because of voltage, as the motor couldn't meet the minimal RPM to close the vane switch.
Then you add in how you maintain your battery, do you have solar or not, and you can see it can be a big variance. I would say people that get 8 to 10 years have a small electrical foot print.