1400 Ah Lithium from cells

[nebster]

Originally Posted by CatNewBee

No, it's the demand.

There goes that dismissing again! Show us your sources, sir.

Meanwhile, I'll give you some stats:

Worldwide lithium-ion production for consumer electronics in 2016: 45GWh. For EVs in 2016: 25GWh.

How many of those 45GWh of consumer cells do you think are LFP? (Hint: almost zero.)

How much consumption can we attribute to DIY/ESS/other bulk storage? (Hint: it's basically a rounding error.)

EV is expected to become the simple majority destination for lithium cells next year.

NCA and NMC are the trending chemistries with the most compelling density and performance advantages for EV. China factories, historically incentivized only to produce LFP, are now shifting production to cobalt chemistries (after the government altered its subsidies and set new density goals that no one thinks LFP can reach).

I don't think LFP is going anywhere -- it has compelling advantages. But it's definitely not where the tip of the spear is today. Or, if it is, it's your turn to prove it.

[CatNewBee]

BTW- if you are curious how a 1000Ah cell looks under the hood:



They use smaller building blocks of 5x200Ah sealed in a bigger enclosure, so there is no advantage to do it yourself by buying smaller batteries and make your own wiring. Just myths, rumors and legends spread around...

[CatNewBee]

Originally Posted by nebster

There goes that dismissing again! Show us your sources, sir.

Meanwhile, I'll give you some stats:

Worldwide lithium-ion production for consumer electronics in 2016: 45GWh. For EVs in 2016: 25GWh.

How many of those 45GWh of consumer cells do you think are LFP? (Hint: almost zero.)

How much consumption can we attribute to DIY/ESS/other bulk storage? (Hint: it's basically a rounding error.)

EV is expected to become the simple majority destination for lithium cells next year.

NCA and NMC are the trending chemistries with the most compelling density and performance advantages for EV. China factories, historically incentivized only to produce LFP, are now shifting production to cobalt chemistries (after the government altered its subsidies and set new density goals that no one thinks LFP can reach).

I don't think LFP is going anywhere -- it has compelling advantages. But it's definitely not where the tip of the spear is today. Or, if it is, it's your turn to prove it.

I simply don't care about alternatives not available yet on the market in this size or not being safe enough for my vessel. LFP is available, I have it and I am happy with it. It is ways better than FLA / GEL / AGM.

I don't want to convince you to use LFP. It's your own risk. You also are free to wait indefinitely until something better is available, science progresses each day. In 100 years probably there will be cells in the size of a D-Cell with 100Ah - I don't know, and I don't care btw. In 100 years I - and most of us - will be humus instead human. I need the battery now.

I can report about my project - and why I made the decision for this set up. Anything else is speculation. Just look up the batteries used in the brand new fleets of electric postal delivery vehicles upcoming in Europe, look at the thousands of e-scooter in china and upcoming in Europe, You'll see everywhere the yellow cells. Just use Google if you are interested in use-cases. I am not here to convince you to go for a particular brand or particular setup and I don't need 45GWh, I am more than happy with my 15kWh.

[nebster]

Originally Posted by CatNewBee

They use smaller building blocks of 5x200Ah sealed in a bigger enclosure, so there is no advantage to do it yourself by buying smaller batteries and make your own wiring. Just myths, rumors and legends spread around...

No they don't, and if they did it would have a lot of downsides.

Look here:

lithium & solar power LiFePO4, FAQ: What is inside the prismatic cell? GWL/Power...

Moreover, there are always legitimate reasons to need smaller cells. There is no single right solution.

[nebster]

Originally Posted by CatNewBee

I simply don't care about alternatives not available yet on the market in this size or not being safe enough for my vessel. LFP is available, I have it and I am happy with it. It is ways better than FLA / GEL / AGM.

The conversation was about why LFP hasn't come down in price. My suggestion is that it may be because the industry is concentrating its efforts on other chemistries. You said that the industry is supply-constrained for LFP due to huge demand.

None of these have much to do with your boat or what you or I should be using today. You seem to have trouble following the argument and have gotten yourself way off track.

Anything else is speculation.

No it's not, it's data gathered by analysts who stay close to the manufacturers. You have a lot of great examples of LFP (and Winston) cells in use, but they are small compared to the global marketplace. And we, building DIY packs for mobile house power, are but a tiny speck in the sea of demand.

[CatNewBee]

Have you seen those following your link?

lithium & solar power LiFePO4, Winston Battery: *Single cells 7000AH and 10000AH ...



I am really impressed 10.000Ah in a single cell. Wow!

Don't you think there might be a demand out there for those and all of the other LFP sizes?
They are build on purpose.

[Maine Sail]

Originally Posted by CatNewBee

I also had my checklist end ended up at the 1000Ah cells as the perfect solution for me.

- I wanted the Yttrium cells because low temp changeability.

I for one would love it it you could provide some independent third party research that shows Winston Chung's claims of sub zero charging to actually be true and 100% safe.

I can't get a straight answer out of them, been hitting them repeatedly since 2011/2012 for actual data to support this, or some clear answers, and all I can say is they waffle, mislead, obfuscate and give different answers to the same questions depending upon when you communicate with them. Nothing that gives me any level of comfort to say the least..

I have flat out had them tell me not to charge their Yttrium cells at below 32°F/0°C and then on another attempt that -45° is safe so long as you stay below a .05C charge rate. Another time I was told it is safe as long as you stay below a 0.3C charge rate. When I ask for data "We no share that." "Do you know of any third party sub zero testing by University or industry that can support this?" "We no have that."..

I have also reached out to every leading university who studies LFP and not a single department I have spoken with or conversed with knows of any actual data nor do they believe it is safe to charge any LFP at sub freezing temps Yttrium doped or not. Their direct competitors laugh when you tell them Chung claims a -45° degree safe charging range. I have even conversed with engineers at massive Li suppliers such as Panasonic for answers to this..

Chung is the one still suggesting it is ok to charge these cells to 4.0V.... We all know how even 3.65V works out, over time, let alone 4.0V..

I would urge caution interpreting any of Chung's manuals without additional third party data..

Here is one of many direct conversations and the type of answer you get from them.

"Question: The manual contradicts itself in a few areas regarding low temperature charging for the LiFeYPO4 cells. In one area it suggest that you can not charge below 0°C and in other areas it suggests that charging at temps as low as -45°C are safe. I have researched at length to find white papers or any institutional research that shows LiFeYPO4 can safely be charged at temps below 0°C. I have been unable to find testing data that confirms this other than in portions of the Winston/Thundersky manual? Do you have any research papers on LYP and cold weather charging you can steer me towards or forward to me? Due to the confusion in the manual, what is the suggested safe charging of these cells at below 0°C temperatures?
A:the minimum safe charging temperature at 3C charge rate is 90℃."




??????


Please share the research, if you have it..

[CatNewBee]

I spoke with some BMS developers and also users about it.
For LiFePO4 it is true, you should not charge below 0°, but
you still can discharge. There are some implementations
with a heat mat under the cells to heat them up using their
own power before start charging.

LiFeYPO4 can be charged and discharged sub-zero. But also they
are not perfect in this matter. The internal cell resistance rises
on cold cells dramatically, so they cannot absorb so many
Amps as warm cells. The issue there is, that because of the higher
resistance, there will be also an increase of temp and if not
done carefully with lower current - it can inflate the cells
to some degree at some point. So it is safe to not bulk-charge
them as long as they freeze, start slowly and increase
current when above 0°C. If you not do that, well they will
first heat up instead of charging...

[kmacdonald]

"Can do" and "Should do" could be different. What are the long term effects of charging in sub-zero temps?

[john61ct]

Originally Posted by kmacdonald

"Can do" and "Should do" could be different. What are the long term effects of charging in sub-zero temps?

Death, as in permanent.

Drawing down near dead flat also.

[john61ct]

Originally Posted by CatNewBee

I am really impressed 10.000Ah in a single cell. .

10.000 = 10 in the US, therefore better to use a comma

[john61ct]

Originally Posted by nebster

I don't think LFP is going anywhere -- it has compelling advantages. But it's definitely not where the tip of the spear is today.

The requirements for a House bank, especially in a mobile context, is a completely different use case from EV.

Aside from lead, LFP is the only safe and economic OTS option for mobile House storage.

Demand for cells will continue to outstrip growth in supply, prices aren't coming down for the foreseeable future, already at commodity levels, just supply chain / logistics / brand trust issues.

But open BMS hardware will arrive, less expensive and more flexible, putting pressure on **packaged system** vendors' pricing.

New battery technology developments take many many years before they are relevant for this market.

Maybe open-hardware DIY EV hobbyists will productize their reverse-engineering projects so junkyard or replacement Leaf/Volt/Tesla can be safely used for low-voltage House use, but short-lived NMC and IMO still too unsafe.

[john61ct]

Originally Posted by senormechanico

I have the add on Pro Remote. I didn't see any option to NO float

Maybe only available for newer / higher priced SCs like the 30XXi series?

[john61ct]

Originally Posted by kmacdonald

LiFePO4 has also proven to eat tow vehicle alternators

Yes, any charge source designed for lead needs careful testing before putting into production.

For alts, a VR with current limiting features is advised, e.g. MC-614.

Or third-party independent charge limiting devices can be put in front of the bank to protect against all charge sources.

[CatNewBee]

I agree, also the sub-zero stuff usually is less relevant for boating.

The batteries are in most cases down low in the boat under the waterline near the bilge for weight distribution, water temp is in most cases above +4°C, you probably will rarely sail in sub-zero waters, most of the time you will enjoy bluewater sailing in the 20-30°C, in bikini-water temperatures - so it is not a killing argument. It is also a benefit for cooling the batteries in hot climates when they are below the waterline. The ocean is your friend there.

Even for RV usage you want freeze-free compartments because of your water tanks on board and you will very likely heat the RV, the batteries will benefit from that.

The batteries are close to where you live, and you are usually also very intolerant to sub-zero temps. Starter battery applications is a different beast they often are located outside in the engine room or separate battery lockers.