Are Lithium Batteries a Direct Drop In?

[TitanMike]

Originally Posted by SlowrideHD

I wish I could have put the upfront cost for my remote solar setup into the Lifepro (BB) batteries but one drawback was the unattended freezing possibilities while I was away.

This is what I have and costs for my battery bank. Sixteen T-105 in a 8S/2P 48 volt config. This gives me about 51 volts/ 225 amps useable (50% discharge) for ~11,475 watts at a cost of $1,840 for batteries. (16@ $115 ea)

To get equiv watts I would have had to use five of the 12v BB in a 5P setup for 13v at 900 amp (80% discharge) for 11,700 watts. Sound about right? But the batts would have cost me close to $5k. On top of the 3200 watts of solar that I put up....whew! And unfortunately, I had to factor in the ease of some thief being able to carry off a light BB battery as opposed to a half ton of flooded acids!

Per a later post you confirmed my suspicion this setup was not for an RV.
Apples and Oranges of course.

Yes, lead acid is still the best, cost wise, for fixed solar storage where weight is not an issue.

As for charging issues during freezing weather issues if BMS has low temp cutoff it wont be an issue.

If cabin is unattended chances are batteries will be kep full on sunny, non- freezing days and when cabin is in use the batteries could be kept warm. One benefit of LiFePo batteries is the ability to keep them in "living spaces" unlike the hydrogen generating lead aid's. Easier to keep from getting stolen too if installed in the attic or other often unused space.

[nayther]

to the OP one thing to understand is that discharging a lead-acid battery below 50% will reduce it's service life but lithium will not be damaged. So if you have 100 amphours of flooded battery capacity you only have 50 amps of useable capacity. I'm considering lithium at some point, probably wear out my two 6 volt batteries first.

[hbneil]

My wife and I just purchased a 2020 Rockwood Mini Lite 2109s. I added a second Interstate SRM 24 as we want to do some boondocking. I also had 190 watt Go Power solar panel with controller factory installed. We've only managed one shake down trip so far. I plan to do a boondocking trip this spring and see how long the 2 Lead Acid batteries & the solar panel will last until the batteries drop below 12 v. If we don't need the furnace much (<4 hr) and it's sunny, we should be able to go several days. If the current setup doesn't last at least 2 days, then I'll need to either get a generator or add more solar.

I've done a lot of research on Lithium batteries, but it seemed a waste to get rid of a new Lead Acid battery. Also, I had a $100 credit at the dealer so the 2nd battery only cost me < $50 net.

More than twice the usable Amp-Hours at less weight and faster charging is appealing. I'll probably switch over to Lithium when it comes time to replace my current batteries.

[TitanMike]

Originally Posted by hbneil

My wife and I just purchased a 2020 Rockwood Mini Lite 2109s. I added a second Interstate SRM 24 as we want to do some boondocking.

When buying new and financing rather than paying cash, why not consider having the Dealer install two Lithium batteries along with a lithium capable converter. Most Dealers around here finance for 15 years so in the end the lithium upgrade would only cost about $12-$13 per month extra in the payment.


Ran into a couple last fall that were boondocking that did exactly that. Ordered their TT with Lithium batteries, upgraded converter, AND a couple solar panels installed on the roof. Said that the monthly cost was small and they then didn't have to worry about later upgrading along with all the wiring issues.

Of course if one's paying cash they see the extra expense all at once but they also have to write the check for the RV too so the extra for lithium/solar is overshadowed by the larger cost of the basic rig.

[NMWildcat]

Well that is certainly an option.
I just will never understand why anybody would finance anything longer than the expected lifetime. And that includes RVs. To me a 12, 15, 20 year loan an an RV is not a good idea. Definitely not a good idea to finance 10 year batteries for 15 years. But that is just me.

Originally Posted by TitanMike

When buying new and financing rather than paying cash, why not consider having the Dealer install two Lithium batteries along with a lithium capable converter. Most Dealers around here finance for 15 years so in the end the lithium upgrade would only cost about $12-$13 per month extra in the payment.


Ran into a couple last fall that were boondocking that did exactly that. Ordered their TT with Lithium batteries, upgraded converter, AND a couple solar panels installed on the roof. Said that the monthly cost was small and they then didn't have to worry about later upgrading along with all the wiring issues.

Of course if one's paying cash they see the extra expense all at once but they also have to write the check for the RV too so the extra for lithium/solar is overshadowed by the larger cost of the basic rig.

[TitanMike]

Originally Posted by NMWildcat

Well that is certainly an option.
I just will never understand why anybody would finance anything longer than the expected lifetime. And that includes RVs. To me a 12, 15, 20 year loan an an RV is not a good idea. Definitely not a good idea to finance 10 year batteries for 15 years. But that is just me.

Depends on the RV, the person, and use. My previous travel trailer was with me for 22 years. Only real reason I got rid of it was grand-kids grew up and went their own ways so I had no need for the bunkhouse floor plan. Still in good shape and I wouldn't have hesitated taking it on a long trip anywhere in the US. I purchased a shorter trailer with slide out that is a lot more suitable for my current needs and if I live that long I see no reason why it won't be with me for the next 20 years.

As for "10 year batteries", that's only the term of warranty. No reason why they won't last a lot longer if one follows the mfr's instructions for care.

Lithium batteries have been around in EV's and Hybrids for years and even with their continued "deep cycling" their lifespan is expected by many authorities to be 10-20 years. Unlike cell phone Li-Ion batteries, the LiFePo batteries are considered to have the longest life expectancy in the "Lithium Family".

Current batteries in EV's are being looked at more and more as "Lifetime" batteries as the technology advances both in chemistry, but in manufacturing. The "10 year warranty" is there because a manufacturer has to put a number on their warranty and will keep it as low as possible in order to limit their future liability. Something to consider, a Chevy Volt (I own one) has an 8 year/100,000 mile warranty on the main battery when sold in 49 States. In CA it has a 10 year/150,000 mile warranty (due to CA regulation) but do you think they use a different battery in CA cars?

Think "Cycles", not years. Most drop-in LiFePo4 batteries have a 3,000-5,000 cycle life expectancy. Do the math and how many years will that amount to for someone who boondocks 30-40 days per year?

[grumpyer]

What NMWildcat said!!!!!!!!!!!!!!!!!!! I will add that I can buy a lot of non-lithium bats. for price of 1 lithium and don't have to worry about theft as much. Good luck on whatever you do!

[TitanMike]

Originally Posted by grumpyer

What NMWildcat said!!!!!!!!!!!!!!!!!!! I will add that I can buy a lot of non-lithium bats. for price of 1 lithium and don't have to worry about theft as much. Good luck on whatever you do!

Good luck getting to my Lithium batteries. They're installed inside the trailer where they're secure, not exposed to weather extremes, and not getting splashed by slop from a wet road.

[babock]

Mine are also inside under my bed. You will need some tools to remove mine so make sure you have a lot of time on your hands!

As far as the temperature considerations, since mine are inside not an issue. Also,the only real temp caveat is charging. You cant charge unless the internal battery temp has gotten down to 24°F. That typically means the temp has had to get to something below that and allowed the battery to cold soak. However, you can discharge them down to -4°F. You just buy a cheap $20 heating pad and then you are fine. Some lithium batteries come with builtin heaters if you live in cold climates and the batteries are exposed to weather.

[hobienick]

If you are on the fence about LiFePo batteries and don't really need them it may be smart to wait. There are some new battery technologies that are supposedly about to hit the market in the next few years. They supposedly have more energy density and are less finicky about deep discharges than current technology.

It looks like we are on the precipice of battery tech being like PC tech back in the 90's. Every time you buy something, it is immediately obsolete. I'm not sure if it will be a Moore's law scenario but patience may be rewarded.

[TitanMike]

Originally Posted by hobienick

There are some new battery technologies that are supposedly about to hit the market in the next few years. They supposedly have more energy density and are less finicky about deep discharges than current technology.

I seriously doubt that the current LiFePo battery technology is finicky about deep discharge considering that they can be "run flat" and recharged fully and still have many multiples of cycle life over Lead Acid tech. Only battery tech we use currently for RV "house batteries" are lead acid and LifePo. The latter could essentially care less about how deep you discharge it as the internal BMS will protect it from damage.

As for "future tech"? Maybe in our lifetime something will be developed that yields better energy density for less cost, along with the safety of the LIFePo tech but probably not in my lifetime. Waiting may be a long process.

[hobienick]

Not as long as you think

https://www.graphene-info.com/graphene-batteries

https://www.digitaltrends.com/featur...gong-ces-2020/

https://www.youtube.com/watch?v=dnE1...JwSXzQ&index=5

Granted, graphene enhances LiFePo technology, but it still is an advancement that is commercially available today and is moving beyond cell phone batteries.