Lifepo4 battery in 1990 Lance?

Please not the SiO2 debate again ;)

SiO2 has the same energy density (volume and mass) as any other lead acid battery. If you want a higher energy density then lithium is really the only way to achieve that.

As for charging, with an LiFePO4 cell you will reach full charge (or at least 95% SOC) with any voltage above 3.4V/cell or about 13.6V for a 4-cell series pack. Going to 14V or above won't get you any more charge, and if anything tends to push the cells out of balance.

There is some excellent test data from powerstream showing just this:
https://www.powerstream.com/lithium-phosphate-charge-voltage.htm

FWC, why do you say Li is about the only way to have more usable AH when you can also do that with SiO2? --not saying they are equal types for all purposes, but just that they both allow low SOC operation.

Also, why do you say his single voltage 13.6v converter is ok for charging Li batts? (AFAIK they require 14.x)

agesilaus wrote:
I would read this current thread before wasting my money on LiB. They make no economic sense for RV owners.
LiB vs 6V

There are lots of other reasons to use lithium batteries besides straight economics (RV's generally don't make economic sense). It sounds like the OP wants more capacity in the same space as his/her current battery and lithium is about the only way to do that.

To the OP, yes you can just replace your lead acid battery with a drop in lithium (look beyond battleborne, there are better value options out there). You will get better performance and be able to take advantage of the advantages of lithium if you upgrade your charger, but it is not a requirement.

You need a charger that will do 14.4ish volts--that one only does 13.6 volts. (you can swap that out for , eg, a PowerMax to solve that) You need a Trimetric monitor or similar to keep track of your AH and SOC, because the voltage per SOC does not change enough to be able to tell your SOC from the voltage like you can now.

Idaho gets cold at times. You will need to solve the cold weather issue with those Li batts. (Some have tried this with heating pads etc.--don't know how well they are managing--you need power to the heat pad, eg)

You would get more usable AH, but not twice as many. The operating range is more like 80% of the SOC vs 50-60% you have now.

I was able to carry more AH worth of batts for the TC by putting batts in the truck bed in front of the wheel wells and run wires to inside. I connected/disconnected those batts when sliding in/out the camper with the camper part way in so I could get at the wires , and when they could reach. (That door some TCs have at the bottom left side that opens into the truck bed comes in handy too)

Another approach is to choose SiO2 for the TC where you get the extra AH same as Li, but no worries about cold temps. That is what our TC has now, but not for the reason to get extra AH. Our reason was to get the high discharge rate they can take (for the inverter to run the MW).

Li can do that too but they cost so much more --although that might be changing since the prices of both Li and perhaps SiO2 are apparently changing in some markets (not "up here" yet AFAIK)

That link takes me to a gmail page.

I would read this current thread before wasting my money on LiB. They make no economic sense for RV owners.
LiB vs 6V