Lipo vs lifepo4

[john61ct]

Originally Posted by hellosailor

Odd, or interesting, that the CALB SE and CA series seem to be different only in that the CA series are rated for a 2C discharge (versus 1C for the SE) while the CA series are designed for backup power installations, and the SE series for light traction--which I would have thought needed to pull higher impulse power loads.
?

Although I think 4x 180Ah cells beats 8x 100Ah cells for [no pun intended] bang for the buck.

From a seller site:

What is the difference between the CA and SE series of the CALB cells?

The CA series are the 2nd generation of the LiFePO4 cells. The SE series are the original (1st generation) of the LiFePO4 cells based in the Sky Energy (Thunder Sky) technology.

The CA series have several improvements*in the mechanical design of the plastic housing and the safety valves. The CA series have also little bit improved manufacturing process and the chemistry.

Based on information from CALB, during 2014 the production of SE series will be gradually reduced and suspended. It is recommended to consider*using CA series for all new projects.

_____
A good writeup from a trusted reviewer on other improvements going from old SE to newer CA.

http://evtv.me/2012/06/battery-jump-shift/


This type of detailed info will be readily available for any cells I would be spending money on.

[Maine Sail]

Originally Posted by newhaul

ok that spec screenshot I posted was for a lower ah rating battery iirc it was for their claimed 80ah unit. A direct question about charging the reply was 1.2C or 120 amp for the 100ah unit. Cells are 18650 on the 160ah unit and prismatic pouch on the 100ah.
I have decided not to purchase from this company due to discrepancies in price between ordering from the person I have been talking to and direct from their automated system. ( automated stated free shipping to my shop. Via sea freight. )
its not the battery but the price juggling that is my red flag.
( not to mention that they preferred t/t or western union for payment. Over even PayPal)
this information I just received this am)

Please read this spec sheet for an A123 18650 LiFePO4 Cell. This is one of the few "legit" LiFePO4 cells that actually meets its 1.1Ah rating if you don't get a counterfeit. While some less legit Chinese cell makers claim up to 1200mAh or in some cases 1500mAh they are usually bogus ratings.

A123 18650 Cylindrical Cell
Cell Ah Capacity = 1.1Ah
Cell Weight 39 Grams or 1.38 ounces each
Cells needed for a 100Ah 3.2V cell =91
91 1.1 Ah Cells = 7.85 Pounds
You now need 4 100Ah 3.2 cells consisting of 91 18650 cells each
91 X 4 = 364 Cells for a 12.8V 100Ah battery
364 cells = 31.4 pounds in bare cells alone, no case, no wall wart, no terminals no wiring.....

All I can do is try to point out the obvious.... You are being lied to and HOSED!

[john61ct]

Originally Posted by newhaul

they hate escrow.com even more.

I doubt it. Just like good US credit cards and eBay, PayPal is basically "buyer gets 100% refund by default" often even when the seller has done everything right.

[Maine Sail]

Originally Posted by hellosailor

"Lets go back to basic physics. Energy density wise you simply CAN NOT fit anywhere close to 100Ah of capacity in that form factor or weight (6.8 pounds)."
Maine, which diploma mill did you get one from? (Kidding!)

Well when you selectively quoteand leave out that we/I are discussing LFP batteries.........

Originally Posted by Maine Sail

Lets go back to basic physics. Energy density wise you simply CAN NOT fit anywhere close to 100Ah of capacity in that form factor or weight (6.8 pounds). Hell you can't even get 50Ah at 6.8 pounds, at 12V with LFP.

LFP = LiFePO4...


Can you explain to us how you can get 100Ah of 18650 LFP cells to produce 100Ah at 12.8V in a 6.8 pound unit complete with BMS........

[john61ct]

Max currents for bare cells in reality come from the chemistry.

Mfg ratings likely way lowballed, maybe lawyers involved. 3-4C rates are fine if your infrastructure can handle so can the cells.

And same with "intended use", whether EV or House bank is up to the buyer, not actually anything to do with the battery.

In all cases we're talking LFP, atomic powerpacks aside 8-)

[john61ct]

Originally Posted by Maine Sail

Can you explain to us how you can get 100Ah of 18650 LFP cells to produce 100Ah at 12.8V in a 6.8 pound unit complete with BMS........

I think only jocularity was intended there.

[Maine Sail]

Originally Posted by newhaul

Cells are 18650 on the 160ah unit and prismatic pouch on the 100ah.

Pouch on 100Ah? 100Ah 18650 Battery DMD

[hellosailor]

"whether EV or House bank is up to the buyer,"
Isn't everything? But IIRC all the electric cars, including Tesla, are using liquid cooled battery packs. And they all will cut off, or throttle back, motor power when the battery overheats. In Tesla's case, too much use of "ludicrous mode" can wake up the "governor" pretty quickly. In a typical boat house bank...one would hope that between the price of good copper cables and the limited space to install electric pizza ranges, there really aren't many ways to put a 10C or 20C load on the batteries. One would hope.(G)

[hellosailor]

"Can you explain to us how you can get 100Ah of 18650 LFP cells to produce 100Ah at 12.8V in a 6.8 pound unit complete with BMS........"
You're not going to be much of a riddle challenge if you meet a Sphinx on the road. The answer to your question is EASY.

Just stuff the 18650's and all the rest into a conventional Mr. Fusion unit. The energy is there, the power is there, how you get it out is just a minor exercise in engineering.

Arabic numbers are sharp and pointy, it is dangerous to throw them randomly about consumers!

[hellosailor]

john-
"A good writeup from a trusted reviewer"
And somehow, that's way more info than CALB-US manages to put up on their own web site. Funny how that works, huh?

[Joli]

I really don't get the rush to move to LFP? FLA works fine if the bank is sufficiently sized and the boat has renewables (solar, wind and water) to keep the bank near 100%. Add in a generator for making water, and charging batteries every few days and it works especially well. FLA is about $1/ah and seems to last 6~8 years. Our bank is down about 15% every 24 hours.

[newhaul]

Originally Posted by Maine Sail

Pouch on 100Ah? 100Ah 18650 Battery DMD

the original battery I found on their site was pouch however now all I can find are the 18650 matrix so another red flag.

[john61ct]

There is a huge community of EV DIY hackers building their own packs for cat, truck and van conversions using all kinds of different cells, and certainly no liquid cooling involved.

Originally Posted by hellosailor

one would hope that between the price of good copper cables and the limited space to install electric pizza ranges, there really aren't many ways to put a 10C or 20C load on the batteries. One would hope.(G)

Maybe not that high, but over 1-2C I can see just in the kitchen, dishwasher, powerful enough food processor, microwave or induction cookers, running concurrently. I can see windlasses getting up there. Some people dream of aircon running off batteries. . .

[john61ct]

Originally Posted by Joli

I really don't get the rush to move to LFP?

And yet that's what these threads are about, in this case comparing LFP to LiPo. If the topic isn't of interest to you, plenty of other threads out there.

Or start one titled "Convince me why LFP is better than FLA", I bet you'd gather some good information if that is actually of interest to you.

[john61ct]

Originally Posted by newhaul

the original battery I found on their site was pouch however now all I can find are the 18650 matrix so another red flag.

I think the point we've been trying to make for some time, is that nothing they claim can be taken as fact, so there really isn't any point in paying their "specs" any more mind.

Move on to at least potentially reliable possibilities!