Energy storage - New gen batteries

[KJINTF]

Thought you might like to see this
Energy storage aka power aka watts
Might be my rig's next battery

Watts aka Power Aka energy

[reed_cundiff]

The primary cause of over-heating of battery banks is charging at to high a rate. This is not likely to be a problem with solar charging. The figures show that charging up to 0.6C should not be harmful. Not sure how we can charge at a rate of 6 kW with a 1400 W solar panel array.

Electric Vehicle folks may charge to 70% SOC at rates up to 10C.

Reed and Elaine

[time2roll]

horton333 wrote:
I understand there are in excess of 200 differing battery chemistries that are based on Lithium, but the comments I have read from the engineers are that any can catch, and do, fire. Whenever you have increased energy density this is something that needs to be planned for.

Spontaneous combustion I understand is pretty rare. Need physical damage or overheat or overcharge the battery. For light use in an RV this should not be an issue.

And of course lead-acid can have it's issues too.

[reed_cundiff]

The only problem with higher voltage battery bank is that you now need a converter (Mean Well in our case) to change 48 V to 12 V and there is a few percent inefficiency there.

We always turn off propane when we travel. However, the solar panels operate the fridge on AC while we travel. We are always circumspect concerning propane, tires, brakes etc. Have been this way for quite a while. Was foot recon 48 years ago and we had a saying "Stay a Lurp and stay alive!"

Reed and Elaine

[KJINTF]

Reed

I agree 100% with going to a higher battery bank voltage if at all possible. However for my current rig I do not see it happening, maybe a future rig but not this one. For the very same reasons you state I went with a PV array of 40Voc and a MPPT controller. It's all about POWER aka Watts higher voltage lower current WAY lower wire losses

Me I'm not worried about batteries starting on fire. Nor am I worried about using my 18 gallon propane tank supplying propane to the frig while driving or the 60 gallons gasoline tank starting on fire. Attention to the details is always required

[horton333]

I understand there are in excess of 200 differing battery chemistries that are based on Lithium, but the comments I have read from the engineers are that any can catch, and do, fire. Whenever you have increased energy density this is something that needs to be planned for.

[reed_cundiff]

One other discussion point found on LFP caravan/boating fora is going to 24 V or 48 V battery banks. This allows using much lower amperage and consequent smaller cabling and lower amperage MPPT controllers.
Reed and Elaine

[KJINTF]

Yes indeed it's LFP batteries we are discussing here

Another link for your reading pleasure
Link

[reed_cundiff]

Tesla and other electronic vehicle manufacturers tend to use LiCo since it has a much greater energy density; however, it can overheat and catch fire.

Lithium iron phosphate is a completely different chemistry/physics. The different LFP manufacturers themselves use different technologies. The technology is developing and improvements have been made since we went to LFP 19 months ago. From what I have read, the charging rate should be below 0.5 C. We have a 9.6 kW-hr battery bank so we should not charge over 4.8 kW. Since we have a 1400 W solar panel bank and have never gotten more than 1330 W to controller, I strongly doubt that we shall charge at to great a rate.

Have been following a number of fora that are concerned with LFP in boating and RV and have yet to find anyone who is not happy with their use. The only arguments are whether to go with a battery management system or with individual cell balancing. This seems to have been a leit motief for 400 pages and 2000 posts on the Sail and Cruising forum. The same seems to go on at several Aussie fora as well along with Northern Arizona Wind and Solar and the Solar Panel Fora.

Reed and Elaine

[horton333]

Places like Tesla, one of the highest tech car companies in the world, still get fires in their cars from time to time and so does every laptop manufacturer out there. Tesla use titanium shields to protect people, they know the hazards. They have extremely advanced charging and temperature monitoring systems, yet still some catch fire. I think they are the way of the future, but I would not go in without investigating the very real issues and making sure the risk is contained.
I note the smaller batteries they advertise seem to have more built in safeguards than this one, may be a better choice. Not sure.

[KJINTF]

As kids growing we all survived the hazards of Pb
I agree it's not good in any way shape or form for the human body or animals
Kind of the reason we no longer have Leaded gasoline or Lead in house paints and greatly reduced lead in shot gun shells
Lead aka Pb has it's place as in tire weights, etc..
Remember when you put your fingers in a pool of mercury? Been there done that

I would venture a guess that tens of thousands more FLA batteries have exploded than Li batteries ever will. As a young dumb kid who survived some stupid stuff I dropped a lit match on top of a bubbling FLA. WOW pieces of plastic and******in the air everywhere and even worse the acid destroyed my cloths and my skin.

Not really feasible with a LI battery but I'm sure some young dumb kid will find a way to get hurt or killed with the batteries.

Agreed Li Power Sources do REQUIRE a much better properly managed charging profile. It's not rocket science, just requires a bit more attention to the details.

PS - Almost forgot to add - Yet another good reason to use a completely programmable solar charge controller

[MEXICOWANDERER]

Lithium is a health hazard. It is used as a medication adjunct treatment for bi-polar disorders. Manic-depression.

Myself, I like to review lots and lots of comments by users before I commit. For one thing charging amperage MUST be limited with lithium. Not an issue with a huge bank but how about a smaller bank and a crocodile of an alternator in a motorhome?

I would need to do a lot more research. I know aircraft have elaborate thermal sensing of each and every cell.

But! Lithium seems to be arriving and I like it! Lead is hideously poisonous for children. Pb should remain in the ground IMHO.

[NinerBikes]

Is lithium poisoning as big a concern as lead poisoning? What about risk of exposure health wise, short term and long term, if the battery explodes... lead acid vs LIion?

[KJINTF]

Glad you enjoyed the link

Battery technology is FINALLY changing
Been 100 years or more without much change it's long past time for new energy storage technology
Wonder how many more years the traditional FLA battery has left?

I enjoyed the "U" Tube link - Sure would be nice to find that DEAL
That's the battery (4 or 5KW/hrs of stored energy) would do the job for me

PT
My friend down the road installed 12 of the 4Kw/hr batteries with a really nice BMS in his home made electric car. They replaced 12 Trojan Deep Cycle 12 Vdc batteries. Far less weight far more energy and should last far longer. The price will come down as volume increases

[pianotuna]

Hi wolfe10,

I was aware that four would be needed. But considering that it would take twice as many AGM batteries the price works out to be nearly the same. The "sticking point" for me before was no one would warranty to -40 temperatures. Theses folks DO!

wolfe10 wrote:

pianotuna wrote:
Hi KJ.

Operating temperature is finally in the range I need. Thanks for posting this.

I could effectively replace the banks with about 5 kwh (400 amp hours) of LI as depth of discharge is 80%.

400 amp-hours

Does the price include battery management?

It looks like it is price competitive with AGM.

Don,

Unless I am mis-reading, that is a 3 VDC battery. You would need 4 in series to make a 12 VDC battery.

[horton333]

That is an interesting site, they have some smaller more self-contained units more in line with the dual AGMs totaling 220 AHs I have been looking at. Price is not competitive, yet, but close enough if I can convince myself they are not a fire hazard I may even try one.