buying Lithium batteries price question

[OverTheTopCargoTrailer]

Hi Dee

Just measure your voltage first.
Ancor wire has a 10% wire chart and a 3% .
Use the 10% to get right wire.always measure voltage.
I would say set for 13.9v to charge lithium.
when it's full disconnect battery from charger, float is not needed.

[lrrowe]

Jerry, if I understand this right, this concept might work, but one still has to manually watch the charging process. If this is true, then that is not really a realistic process.

[abqlloyd]

With a good charger there is no guessing. The charger recommend by the folks at the link provided in this thread is about $500. It's specific to the voltage and charge profile of lithium. I did some research on using Midnite Solar MPPT for lithium and decided that most MPPT aren't really configured for lithium - especially the newer chemistry. I found a solution to buck and boost the voltage as determined by the BMS off of an MPPT and it was another $400. There's a video on YouTube of a guy who fries his cabin lithium bank with his Outback80 because of voltage issues. The BMS is basically tiny charge control circuits for each of the cells in parallel to ensure the pack stays balanced and healthy and isn't overcharged.

[MtnDon]

I agree Bob. Too much at stake ($$$) to use the personal observation and manual disconnect process for me.

And, for me, the use of extra wire length to compensate for a slightly too high charging voltage smacks too much of a band aid approach that I could not bring myself to do that. But then I also believe that charge controllers, battery chargers of all types should have connections to the batteries that are dedicated voltage sensing wires. Reason: If the wires from charger to batteries are not huge to the point of having no practical resistance then the voltage reading at the charger will have suffered voltage drop and could be slightly low. I know, another anal indicator.

And, abqlloyd is on to something that bothers me too. None of the presently available solar charge controllers are really best suited to LFP. Because LFP does not need Absorb and does not need a Float a band aid approach is used. A charger that is truly best for LFP should, IMO, have a total shut down when the battery upper voltage set point is reached. It should go from Bulk charge to Off; no Absorb, no Float. That is what my lithium tool battery chargers do. It is just going to take some time for this to happen in the renewable energy field.

The lithium battery manufacturers all (mostly?) seem to indicate their batteries are compatible with present solar charge controllers. That is, IMO, because their primary focus is on selling their batteries. Call me a skeptic

[abqlloyd]

I can speak to the $1,600, as you posted the link. They sell a 100ah, 12v, RV battery with charger with BMS for about $1,600. Prism cells, 3C discharge.

[abqlloyd]

http://www.electriccarpartscompany.com/ ... p_111.html

This is where I got the figure.

[Deediggler]

So we've established that lithium batteries are more affordable then ever. What about simplicity for the amateurs? I want a turn key system with will be easy to install with out an electrical engineering degree. Lots of info on regular lead acid battery banks. I feel like I can accomplish a system using regular batteries, but lithium seems more complicated with charging and I've already bought a progressive dynamics converter. It just scares me so I'll likely go with what I already know works. Unless someone makes a lithium kit for dumbies.

[abqlloyd]

I have a decent trailer with dexter torsion axles, XPS insulation, upgraded water resistant paneling, radial tires, Midnite Solar MPPT, Blue Sea electronics, Fantastic Fan, innerspring mattress, energy star appliances, LED lighting, good wiring, laminate floors, ceramic heater, and a host of other decent parts to go with my perfectly functional FLA batteries.

It isn't about money or which is the better technology. It's simple cost-benefit analysis. For this project, the dollars could be better utilized someplace else.

Hey, did you know if you stuff a $15,000 crate racing motor in a $6,000 used Ford you can go as fast as a new Porsche? Why does anyone ever by a Porsche?

[abqlloyd]

12v Pack made of 4 each 100Ah 3.2V Lithium LiFePO4 CALB Batteries USA STOCK! https://www.amazon.com/dp/B00SC6PEO6/re ... Zub0YBD3PQ
https://www.amazon.com/dp/B00SC6PEO6/re ... Zub0YBD3PQ

[Deediggler]

So I think I'm gonna bite the bullet on one of these bad boys.

http://www.electricmotorsport.com/ev-parts/batteries/lithium/gbs-12v-4-cell-200ah-lifemnpo4.html

Now I have to figure out a complimentary solar charging system for it.

[abqlloyd]

The Midnite Solar Classic is rumored to be acceptable. There's also a rumor of an impending firmware update specific to lithium. I have been researching charge controllers today.

[OverTheTopCargoTrailer]

So I think I'm gonna bite the bullet on one of these bad boys.

http://www.electricmotorsport.com/ev-parts/batteries/lithium/gbs-12v-4-cell-200ah-lifemnpo4.html

Now I have to figure out a complimentary solar charging system for it.

Dee

I would recommend you buy from direct source importer unless you live in AZ and would need to pay sales tax....
Also I would buy 2 x 100 and reconfigure them into 2P4S with 8 cell boards @ $8.95 each
So thats $1240 same 200 AH and $64 for mini BMS
Cheaper than your $1390

http://elitepowersolutions.com/products/product_info.php?cPath=25&products_id=92

or call them & talk to Rick.....

I think their shipping for 2 x 100 is around $80 ??

Another option is to buy 8 x 100AH CALB cost $1072 .....plus shipping


I would get the 120ac charger I linked above, it will let you do 12 volt & also charge single cells to balance then if needed
Kill 2 birds - 1 stone.

http://www.mastechpowersupply.com/volteq-power-supply-hy1520ex-15v-20a-for-charging-lithium-batteries.html

The GBS is cheaper at $69 , but is not adjustable and will not allow you to do a single cell at 3.3v , also its 6 amp vs 20 amp
so it would take 33 hours to charge 200 ah vs 10 hours

Also if your willing to spend around $500 the solar charge controller Outbackflex Max 80 works perfect, set absorb to 13.9v and forget
it will allow you to connect 1,000 watts in panels to 12.v batter, 2,000 watts solar to 24.v battery

Cheers OTTCT

[PaulC]

Just so everyone knows, this thread is being monitored closely.
Cheers
Paul

[MtnDon]

The Voltec charger is a nice unit, but is not a plug 'n' play unit like the chargers most folks are familiar with. It is not actually a battery charger but a lab quality power supply that has many uses. The ability to dial in the precise voltage and amperage is what makes it a great tool. That same ability is what can turn it into a source of battery abuse and/or destruction in the hands of the careless or the uninformed.


I had no idea the FM series Outback charge controllers would actually go silent when a lithium battery is attached and reaches full. That is not documented=d in any of the OB materials I have read. So that was interesting to learn. Seems to me that was good information that could have been passed along earlier in a friendly manner. That would be in keeping with the in the sharing information that comes from first hand experience; a part of the share-what-we-learned camaraderie here in the TD and TTT world.


Yes I want to run my FLA batteries, both cabin and trailer, until they are not worth the effort involved. What's the crime in that? In the meantime I'll follow the stories of personal experiences with LFP, here and a few other places. There are satisfied users. I've also noted one of my issues with LFP, though... that of charging at below freezing problems. That seems to be glossed over by many who sell the product. At the very least that shortcoming is buried in the tech data at times. Everyone ought to be aware of that up front as we are used to using and charging our FLA and SLA batteries at temperatures well below freezing. OK, the trailer batteries can easily be kept warm when charging. The cabin, OTOH, will need some reworking, rewiring and remodeling in order to place LFP where they can be kept warm for charging. My problem, my situation, but it is something I'll have to deal with at some point if I want to go LFP, and someone else could have the same issues. So I mention it to inform.


Anyway you cut it there is still the up front cost. Yes, over time the LFP can end up being less expensive because of longer potential life. But I'd still have to spend the bigger dollars today and I do not have baskets of cash laying about.

[PaulC]

I am starting to get a little tired of your continual denigration of those who choose to stick with what they know OTTCT! Continue with that way of arguing your point and I will lock this thread.
Paul