My Amp doubt

[Sunking]

So why did you say they don't sell to the general public, or am I missing something?

Yep I am not interested in Polymer, LiFeP04 USA made 10,000 cycles. That would be A123 System.

[greenHouse]

No I can find Polymer all day long, but who wants them? At 500 to 1000 cycles they are worthless for EV or RE. FWIW I have a 150 AH 48volt LiFeP04 volt in my racing golf cart. Unfortunately they are Chi-Com Thundersky.

So why did you say they don't sell to the general public, or am I missing something?

[Sunking]

You're joking, right? Because you and Derick are incapable of using "Google"?

No I can find Polymer all day long, but who wants them? At 500 to 1000 cycles they are worthless for EV or RE. FWIW I have a 150 AH 48volt LiFeP04 volt in my racing golf cart. Unfortunately they are Chi-Com Thundersky.

[russ]

I have zero interest in searching for those batteries - don't need them.

Those particular suppliers Sunking mentioned have failed in grand fashion - after much publicity while they were trying to line up suckers or rather 'investors'.

What battery suppliers will be around in five years? Mainline companies only most likely. Tesla went with the zillion batteries as last choice I suppose. I can't imagine them not preferring a much smaller number.

The chip on your shoulder is quite heavy it seems.

Russ

[greenHouse]

Quote - 'Huh? They aren't the only ones who make Li-Ion batteries, you know'

Then name a few names rather than just a wise ass answer.

You are playing gottcha!

You're joking, right? Because you and Derick are incapable of using "Google"?

In one minute of google'ing I found this page -- http://www.batteryspace.com/ullisted...-ioncells.aspx -- filled with them.

Go forth and buy!

[russ]

Quote - 'Huh? They aren't the only ones who make Li-Ion batteries, you know'

Then name a few names rather than just a wise ass answer.

You are playing gottcha!

[greenHouse]

So let me know when A123 will sale Pouch and Prismatic batteries to the public.

Huh? They aren't the only ones who make Li-Ion batteries, you know.

You need to work on your supply chain, or perhaps not buy them as "the public". Are you trying to get them for your EV work? Or your job-job?

[Sunking]

Not all Li-based batteries are small factor tubes. It's possible to built a Li-Ion cell as a plate that has a much higher capacity than a tube, then stack those plates into a single cell.

So let me know when A123 will sale Pouch and Prismatic batteries to the public.

The Tesla is about 6,000 2AH 3.6 volt cells, but those are all small cells designed for laptops.

6831 to be exact.

[greenHouse]

You are talking packs, not cells.

Not all Li-based batteries are small factor tubes. It's possible to built a Li-Ion cell as a plate that has a much higher capacity than a tube, then stack those plates into a single cell.

The Tesla is about 6,000 2AH 3.6 volt cells, but those are all small cells designed for laptops. Tesla went that route based on the safety experience with those cells, and the fact that they have become a commodity.

[Sunking]

Thundersky also have a 12v 90ahr battery MODEL NO：TS-LP12V90AH My guess then you only need about 11 in parallel to get 1000 ahr??

You are talking packs, not cells.

[john p]

Sunking I wish you were in purchasing dept here . If I ask for 20 lead acid batteries here to experiment with I get only 10 if you were here could ask for 20 and get 80.

[Sunking]

Sunking ,care to tell us how you arrived at the figure of 8000 cells??With Lithium to make a 12 volt 1000 AH string can require up to 8000 individual cells.All the cells I have used are nominal 3.5v at 10ahr.

Simple John by using the same extremes you are. How many 3.6 volt 2 AH cells does it take to make a 12 volt @ 1000 AH?

It takes 4 - 3.6 volt cells to make a 12 volt @ 2 AH equivalent string right. You would need 500 strings to get 1000 AH.. or 4 x 500.

Oops, my bad, I made a mistake, used pencil and paper this time instead of protein computer It would take 2000 cells. None the less the point is the same, it takes a lot of fricking expensive cells which you had better protect with some form of BMS.

But the real main issue is price. For now Lead Acid will dominate the RE market until the economics go the other way.

[Sunking]

Dereck,

Well ... that's true for trivial batteries and for systems designed not to reach 100% SOC, but it's not true -- and becomes very complicated, very fast -- for batteries that are useful and need to reach 100% SoC.

How is it complicated? To go from 90% to 100% requires the second stage charge which is constant voltage until charge current decays (tapers) reaches 3 to 5% of initial charge current. No more complicated than the 2nd stage (absorption charge) of a 3-stage charger lead acid battery charger. It is the exact same algorithm and requires the exact same hard and software. All you are doing is eliminating one stage (3rd float stage) and some expense. Sounds simpler to me and I know is less expensive.

[john p]

Sunking ,care to tell us how you arrived at the figure of 8000 cells??With Lithium to make a 12 volt 1000 AH string can require up to 8000 individual cells.All the cells I have used are nominal 3.5v at 10ahr.
Thundersky also have a 12v 90ahr battery MODEL NO：TS-LP12V90AH My guess then you only need about 11 in parallel to get 1000 ahr??

[greenHouse]

Dereck,

Well ... that's true for trivial batteries and for systems designed not to reach 100% SOC, but it's not true -- and becomes very complicated, very fast -- for batteries that are useful and need to reach 100% SoC.

NiMH require thermal sensing at any useful level of complexity because the activation voltage for the chemical reaction decreases with temperature -- meaning, warmer cells charge faster. And without something that can monitor multiple zones within the pack, you could be frying some cells and not charging others, and have no clue at all which is which.