Turnigy 4s 5Ah Hard Case 20C Lipo, review in the works

[mattetjus]

I just received 5 packs of turnigy 4s 5000mAh hard case batteries and will write up some info about them here.

link: (Hobbyking / DE Warehouse)
http://www.hobbyking.com/hobbyking/stor ... ouse_.html

Starter up info
They came well packaged, neatly bubblewrapped and had the following resting voltages:

Temperature ~ 22'C
Pack1: 15.37V, 1.1: 3.85V, 1.2: 3.81V, 1.3: 3.85V, 1.4: 3.85V
Pack2: 15.38V, 2.1: 3.84V, 2.2: 3.84V, 2.3: 3.84V, 2.4: 3.85V
Pack3: 15.34V, 3.1: 3.84V, 3.2: 3.83V, 3.3: 3.83V, 3.4: 3.83V
Pack4: 15.37V, 4.1: 3.84V, 4.2: 3.84V, 4.3: 3.83V, 4.4: 3.84V
Pack5: 15.39V, 5.1: 3.85V, 5.2: 3.85V, 5.3: 3.84V, 5.4: 3.85V

i will hopefully finish Discharge and Charge Curves before my vacation.

[Pure]

Very cool. The numbers look promising so far.

I would really like to see someone buy one or 2 of these packs for the sole purpose of cutting them open to see if there is any indication of them being composed of damaged or B grade cells.

There just has to be a reason why they are so much cheaper yet enclosed in a plastic case.

[grindz145]

As a data point, I just received about 12 of these for a buddy. Overall I'm thrilled, but as these things go there are tradeoffs. Two of the packs I received had damaged plastics from shipping and out of the whole batch, there was one cell that was about 150mV low. All in all, these are the biggest steal going for ebikes (or damn near any purpose really)

[iovaykind]

I got ten of these. They were extremely well balanced when they came. These are probably the best bang for the buck, in terms of wh/$. It's a good point that Pure made. Maybe someone can test it, but I'm not willing to open up my packs when they all seem to be working fine. And if HK really did something like that, it'd be a pretty huge lawsuit depending on the consequences in accidents and the like. I really doubt there's anything wrong with them, but no one really knows why they're so much cheaper than other packs that don't even have hard cases.

[mattetjus]

I've been having some trouble with my BMS-Evaluation Module (bq78pl116), got a cell down to ~1V;
I was also a bit dumb there and assumed a bad cell, trying out another pack with the result that over night another cell went low voltage on me; this one though seems to be usable still.

Anyways, i haven't been able to do much of experimenting with the cells themselves.

All except the two deep discharged ones are still hovering at around 3.8V, so they look ok.

[auraslip]

I just ordered 10 as well. I started a thread about paralleling them cheaper and easier by making balance boards with stripboards.

I'm really curious about opening them up. The cases take up as much room as a 6s pack almost!

[mattetjus]

edit: img size

[Ypedal]

can you make those just a little bigger ?... i'd like to view them on my 50" plasma lol....

[auraslip]

lol.

how did you pop the cases off? I just got 10 of them yesterday. They all seem in good shape.

- Open box, inspect for physical damage
- Plug in celllog / HK ballancer and check cell voltages
--- If all cells are in the 3.7 to 3.9v range, all is good so far.. if any are way off, make note of them on the pack..
- Plug into charger and fully ballance charge to 4.20v per cell
- Run a discharge cycle while monitoring cell voltages with cellog gizmo or HK gizmo, i like to use this :
http://www.ypedal.com/Lbd.htm

--- If all cells deliver rated capacity above 3.0v on the first cycle, you got a good healthy pack

- Charge again to full 4.20v, let pack sit overnight, good healthy cells will retain 4.18v + overnight.. bad cells will drop to 4.15 or less..

Then you cycle the cells with more amps and manually touch the packs feeling for hot spots.. if all checks out.. Rock on !

Using ypedals advice with them. I'm on step 4.

[ohzee]

hold on breaking out the projector ;0)

[Arlo1]

I have 25 of these pacs and all is great so far! I put 10 of them in my back pack and 15 in the box on my brothers bike and went all over town the other night lol.

[auraslip]

On the tester. cell-log shuts the relay off @ 3.3v.
Unfortunately I don't have a watt meter right now, so I'm going to log the capacity I put back in the cell using the imax.
Unfortunately, the IMAX balance charges the cells up to 4.24v!
Probably not a big deal to leave them sitting like that overnight, but I don't like the idea of doing that.

[mattetjus]

lol.

how did you pop the cases off? I just got 10 of them yesterday. They all seem in good shape.

...

I used the tip of a screw driver in the corners (the side where the cables exit has no boom-boom-pouches, so, i'd suggest to start there) - i janked it in a few milimeters, not all the way through the plastic casing - there is a little edge half way which was enough for me, and "screwed" the plastic open. There was a weak little popping sound at which i moved the screw driver a bit sideways to open all the way around

[iovaykind]

These are back in stock!! WOW. they've been on backorder for so long!

[auraslip]

Testing at ~2c discharge from 4.15v-3v


1-4

5-8

9-10

[iovaykind]

I would put anything under 3.5v to be yellow and under 3.0v to be red.

[SamTexas]

Testing at ~2c discharge from 4.15v-3v

Thanks for the discharge graphs. What was the beginning current draw on the 2C discharge? What was the ending draw just before the test was terminated?

If you have, can you also post the charge graph(s)?

[auraslip]

Load was 2 50w mr16 halogen bulbs in parallel. Load was around 10a.

[SamTexas]

Thanks, do you have plans to test them at 4C or higher? I'd be interested in knowing the difference in energy capacity between 2C and 4C or higher.

[iovaykind]

Just picked up another 5 packs! These things are great, now I'll have 20s3p 15ah, hopefully enough for a 30 mile route I want to try one day!

[parabellum]

I'm buying them bit by bit since 2010. Only 1 dude cell in over 50 packs and 1 was slightly different resistance but same capacity I opened about 15 and all cells look equal and not refurbished.

Edit: First cells came really underrated, up to 5.6Ah, last packs are closer to 5Ah at 1C discharge rate

[bobale]

So, how much capacity those 4S hardpacks shoud have when they're new? Today, first time after 500 miles, I've managed to extract 208Wh from 12S1P, discharging from 4.11V to 3.60V per cell. My Turnigy wattmeter measures both current and voltage right, so Wh nuber should be also correct, right? I've never managed to extract more than 160Wh from my ~50 cycle 12S pack, so I have no idea how I've managed more than 200.

[iovaykind]

Well 12s means you got 3 hardcase packs. Each one holds 74wh so you should actually be able to get at least 200wh out of them. 222w if 100% DOD. Nothing special about your statement that warrants attention

[bobale]

Discharging to 3.6V is hardly 100% DOD.

[iovaykind]

Pretty close. Not to mention some packs have had more than 5ah.