Lithium Ion vs Lead Acid

One thing I'm looking at doing in a few years is making a solar trailer. This way, I can put a large amount of AGM batteries between two heavy duty axles. Since this system will be connected to the motorhome via an inverter, I can go up in voltage with the batteries without worry inside the trailer. 48 volts is nice because I can safely use skinny wires, and I can get a DC-DC converter for 12 volt appliances (although I've yet to read about anyone on rv.net having any success with one, which gives me pause.)

The ironic thing is that reliable, energy-dense (per volume) batteries would fundamentally change things for the better... but yet, there has yet to be a single significant improvement with battery tech since the '90s and the lithium variants that helps density. Supercaps are nice for speed of charging/discharging, but energy density is the big thing.

I remember paying 2,200 dollars for a Compaq computer that had less capability than what a cell phone has today. 25 MHz, 4 megs of ram and a vast 155 Mb hard disc.

There is insanely intense worldwide competition and effort being put into developing lithium storage. Hundreds of billions of dollars. I do not expect anything less than astonishing results. Selling price will become cut throat as hell like with LED lighting. Adios, toxic and heavy lead and sulfuric acid.

mlts22 wrote:
I wonder if there are any battery technologies that look promising.

Yeah, Lithium Ion. :)

I wonder if there are any battery technologies that look promising. Supercaps charge fast, but don't have that much energy capacity. I've seen others, but they require the battery to be at a very high temperature.

Of course, there are flywheels, but those are not exactly vehicle friendly. Maybe Velkess's design, but they have been quiet after their kickstarter was funded.

I'm sure there is a usable battery technology that is RV friendly out there. Oh well... I'm not looking forward to buying AGMs, but it seems that for this application, it seems to be the best way of doing things.

The way you disable a old LI battery is to soak it in salt water.

bob_nestor wrote:


Still? Lithium-Ion doesn't play well with salt water environments ...

Bob,

Lead acid cells don't do well with salt water either! (Think, "I love the smell of (chlorine) in the morning" :D )

As a retired 24 year US Navy Submariner I don't see anything here that is persuasive about the Lithium Ion cells on a boat if the battery needs to be replaced every couple of years.

We can now build a nuclear reactor to last the life of the boat; a battery needs to last as long as major refit cycle is for other equipments.

YMMV

LiPo's at this time are a whole lot of expense (10 times the cost of flooded cell Lead/Acid) for a rather marginal benefit in charging times, life.

I fly model planes powered by batteries.

Started out with NiCad, progressed through NmHi, now use LiPo. Each change resulted in a great advantage in power to weight (much more important in a plane than an RV). I suspect within a few years, LiPo for an RV (and more general use) will make sense, but at this time, its just a cute idea looking for a sale.

Regards,
Doug

Chris Bryant wrote:
Progrssive Dynamics just came out with the Inteli-Power® PD9100L Series 12- & 24-Volt
Lithium Ion Converter/Chargers.

Good find! Looks like the 12V versions range between 30-80 amps.

Progrssive Dynamics just came out with the Inteli-Power® PD9100L Series 12- & 24-Volt
Lithium Ion Converter/Chargers.

smkettner wrote:
mena, the replacement has been nicknamed the lizard battery for the new heat tolerant electrode material. Time will tell if it holds up significantly better. Still just ambient cooling unlike most other EVs with active temperature management.

Read the new one's would be liquid cooled as well. Guess I need to find some more sources.

atreis wrote:
They've come down a little... (But are still quite expensive.)

LiFePO4 100AH for $1,300

LiFePO4 200AH for $2,400

What's funny is that the 200Ah battery would be enough for most people and have more usable capacity than two 6V GC's (you can use 80-90% of LI's capacity).