To get that capacity you need to get roughly 800 amp hours of AGM (at 50% usable), or 500 amp hours of lithium (at 80% usable). If we take the numbers above for simplicity sake (it’s difficult to directly compare them, as the packaged batteries come in different sizes), the upfront costs we were comparing were:

  • 800 amp hours of 8D AGM – $1840
  • 500 amp hours of lithium – $3100

Things look bad for lithium based on upfront costs.

For those of us full timing and/or anticipating a lot of unplugged time in our RV – this is where the lifetime costs start to look promising.

Laboratory results indicate that we should expect to see 2,000 to 5,000 cycles out of a well cared for LiFePO4 battery bank. In contrast, even the best deep cycle lead acid batteries are typically only good for 500-1000 “deep” cycles