A small commercial.

I have purchased the Thunder Sky cells from:

GWL/Power Group - EV & Power Solutions
c/o i4wifi a.s., Prumyslova 11, Praha 10
CZ-10219 Czech Republic, European Union
auto88(at)auto88.cz

You can see a lot of their products at: http://www.yttrium-power.com

Disclaimer: I have no affiliation with the company, but they have treated me in a swift and very professional manner.
They did require payment before delivery, which tends to turn on all my alarm bells.... I did quite a bit of research on them (aka googling), and they did seem genuine enough - so I went for it.
They have responded quickly to my (sometimes) stupid questions ;-)
I did recieve a discount for promoting them, so make up your own mind, but I will, and can, recommend them.

Mounted cells.

Pictures with comments can be found here.

Raw data.

Table with link to raw data can be found here and here.

Unpacking and visual inspection.

Date: May 12'th 2010

picture The 68 LFP90AHA still unpacked   picture Apparently some transport damage.
picture One damaged cell. The clear liquid is visible on the side of the cell.
According to the friendly people at GWL/Power Group the liquid is:
"...an anti-oxydizing liquid to protect the cell against degradation caused by the reaction with air (or Oxygen). The cell will continue working, but it will not last 20 years. In may get oxidized internally after some time depending on the environment. If the cell is "closed again" the cell will work fine".
picture Another picures of the same cell.
picture Crack at the positive terminal.   picture Crack in the side by the negative terminal.
picture Same crack as on the previous picture but from another angle.   picture Part number of the damaged cell.
picture The neighboring cell that perhaps did the damage.   picture The cells below the damaged cell.
picture The cells below the damaged cell.   picture One of the wood boxes - no visible damage to the cells.
picture All 67 non-damaged cells ready for initial charge/discharge/charge cycle.   Part numbers List of the part numbers.
The cells are made up by three different part number series. Two from 14'th October 2009 (091014) and one from the 26'th og February 2010 (100226).

Initial charge and capacity test.

Date: May 24'th 2010

picture The test setup. The power supplies (only using one) are located to the left. The load on the right. And the Agilent data logger is on the top shelf.   picture The power supply.
picture The load (up to 3kW).   picture A cell attached to the charger.
picture Another cell attached to the load.   Initial cell data. List of the Initial Open Cell Voltage (OCV), Initial Charge, First full discharge and charge cycle.
The list is work in progres and will be update when the data is ready.

Date: June 7'th 2010

The first 10 cells have been charged, discharged and charged and it took 10 days... So if I want specific data from each cell, and mounted in the car before August, a new approach is needed.
I did 5 from batch 1 (091014-F18311 -> F18342), one from batch 2 (100226-F20341 -> F20351) and 4 from batch 3 (100226-F20466 -> F20490).
This mix was due to the fact that I am going to 'buddy-pair' the cells in order to get at uniform battery. So the total battery will be 32 series connected buddy-paired cells.
My luck was that batch 1 has 32 cells and batch 2 and 3 performes similar (afaics). So it looks like I can have 32 batteries (2 paralleled cells) of approx. 3.2V/194Ah each.

The next step will be 2 steps more or less... I will pair up the cells I have measured and connect them in series.
This should give me a battery of 16V/194Ah and I will test this battery with a 0.3C (60Amp) constant current discharge/charge cycle.
From this I hope to gain two things:
  1. An idea about the performance of the buddy-paired cells - can I expect to Ah1+2 = Ah1 + Ah2?
  2. How will similar cells (batteries) perform in a series string?
I intend to bulk charge/discharge a series of cells and the do the last 4 - 5Ah individually one cell at the time.
The bulk charge will be 30Amp into 10 cells until the first cell reach 4.0V.
The discharge will then be done witn 30Amp until the first cell reach 2.8V and the doing the rest individually.
The 2 times 5 buddy-paired cells

Date: June 9'th 2010

The cells has been paired up and put through a discharge/charge cycle. Data can be seen here.
A new set of 10 cells has been put in a single string (32V/90Ah) and are being put through the charge/discharge/charge cycle.
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