Daly BMS gone crazy..Update Opinions

Good video. I did not understand his capacity numbers in Wh. BB says 100% resting voltage is 13.6v so a 100AH batt would be 1360 Wh when full.

shipping rating is based on "nominal" 3.2 v cell x 4 =12.8v so Wh is rated as 1280.
I don't understand his Wh calcualtions. Perhaps somebody could spell those out here so I can do it in slow time. Thanks.

He gets 120AH, but still zero% is 10v which means if you are down 100 out of 120, voltage would be 12v not 10v, since you are not at zero yet.

Very confusing!

Unless your pushing serious current the prismatic temps rise very very little or atleast mine don't 100-200a or so (charging/ discharging at 0.2c-0.4c).

As cells discharge and charge heat is produced - Cylindrical cells purportedly stay cooler because of the air space around them.

3 tons

It's all in the sales pitch.

This should answer BLF13 question from before about BB. In the attched video It's torn down so you can see what's in the magic box at 5:16.
30 cylindrical cells in parallel for a total of 120 cells. BB rates the battery at 1,200wh "BUT" true capacity is 1,305wh which is why you can run their battery down 100% It's over built. ;)

https://youtu.be/G5E30u-66VI

Just reading on Battleborn,I noticed this comment made by them..

We’re also often asked as to why most lithium battery companies say not to bring their batteries to a full charge or below 20%. The batteries use cylindrical cells that can be drawn down completely. Other lithium batteries typically utilize prismatic or block cells for their chemistry. Avoiding the use of prismatic or block cells allows our batteries to have a longer life span and to achieve 3,000 to 5,000 life cycles.

Unless I'm misreading it,it suggest it's the prismatic that shouldn't be drawn below 20%..Kinda a diss on prismatic true or not..

jaycocreek wrote:
I'm surprised someone hasn't brought up cylindrical vs prismatic lifepo4 and there differences..Battleborn uses cylindrical..

the major difference is economy of scale and how safty functions work in them. and the method in which you attach them to make a 12V battery. for the average person building a cylindrical isnt easy. anyone who can hook up a mutliple battery system in a rv can build a prosmatic set up. there is a tiny but more energy dencity in the cylindrical but that alo come with higher weight and size for the finnished battey. battery cooling/heating can be done easier with the cylindrical ones also but when you need either of thoes its far and few between, the adverage person who is going to build is never going to constantly charge and discharge at 1C as most will build a 280 or multiple smaller ones and I think would le luckey to see 0.20C in a nirmal rv.

Steve

pianotuna wrote:
Steve,

My concerns are for the "drop in" folks who don't realize that LiFePo4 require strict parameters to be met.

Your charging example is one such number. Alternators may (or may not) fail, due to exceeding their duty cycle. My understanding is that a 180 amp alternator (larger than I have) has a continuous rating of about 60 amps. Li are "greedy" and can charge at 1 C. Most folks would want at least 200 amp-hours of storage.

Any battery can be made to work well in an RV and if the end user is knowledgeable LiFePo4 can be marvelous.

I think that anyone following this thread is going to be a happy owner. But for others who don't have inquiring minds.....not so much.

I dont thing the requirments are any more strict than normal batteries or SiO2. maybe even less strict in some ways. normal batteries you need a three stage charger with desulphacation, and you need to watch water levels, make sure it is fully charged below a spicific temp or it will freeze, dont let it get to hot, and only use 50% .. miss any one of these and you can kill your batteries in short hand

SiO2 has some of the same but more strict in some, dont charge more than 25amps (average camper has a 45 to 75 amp charger), dont use to hot, dont use to cold (although that one is there shining star), dont run below 20% SOC, I am not sure of there charging profile requirments as frankly it is hard to find real info about them asside from sales sheets.

Li dont charge or discharge to cold (very managable targest for most) only need a single voltage charge requirment, dont run to hot (very close to SIO2 upper limit depending where you look its the same give to rake 5 degrees.) no levels to check, no worry about vibration no worry about running it down to 0% SOC as thats what its cycles are based off.

so in a way there are two that are , not nessasarly more strict but less optamal for a small group of people but he rest would more than make up for them. the altanator example the only way some one would be able to do that is to bypass there whole system with new wires than are not fused, and eeven then on the newer batteries I think the smart altanatore would shut down (but Im not sure) at anyrate the charge profile coming off a altanatore in a car isnt what we want for any battery thans why I have it disconected on both my 5th wheel and camper. I am going to actavate it again but with a little 20 or 40 amp dc to dc so I can controle the charge profile. my 6V GC batteries in my 5th wheels didn't last 16 years and counting for no reason. you have to treat any battery tyoe right and they will treat you right.

Steve

Steve

time2roll,

In that case, I'd be better off buying in Canada. And I get a "free" trip to pick them up!

But it was a great thought! So thank you.

pianotuna wrote:
3 tons,

The FIND goes to FWC not me.

I can't see me ordering 50 of them. But it is certainly worth following up.

Maybe I could start a "buyers club" on Facebook!

Make them an offer for 10 at the unit price of 50 or you have to think about it. Nothing to lose. You can click and buy any day of the week.

pianotuna wrote:
3 tons,

The FIND goes to FWC not me.

I can't see me ordering 50 of them. But it is certainly worth following up.

Maybe I could start a "buyers club" on Facebook!

Of Course Sir, I was remiss in my duty - Many thanks to FWC

3 tons