New Turnigy liFe packs

[swbluto]

I purchased a sample of these for testing and found that at 65 Amps, the voltage dropped to 4.4 volts from a nominal 6.6 volts which is about 2.2 volts per cell.

Since it's a "4.5" ah pack, that should be 65/4.5 = 14.4C. Comparing to an a123 cell at http://www.fmadirect.com/support_docs/item_1229.pdf, the a123 cell has a voltage drop to 2.78 volts from 3.3 volts at 14.6C. (3.3-2.2)/(3.3-2.78) = 2.11, so it appears that these cells are about "2.11" times worse than a123 cells. So, if a123 cells are considered "30C" cells, these are more like 14C cells.

However, this test was performed on a battery pack with no charge/discharge cycles (As far as I'm aware) on it, so performance might improve with use.

And to confirm, these are genuine flat-packs and not cylindrical cells.

 

[johnrobholmes]

In RC cars people seem to be having better luck, and results similar to a123 M1 cells. BUT, the loads are more like burst- burst- burst instead of a constant load. That may very well be the key performance factor.

 

[will_newton]

the loads are more like burst- burst- burst

interesting way to control the duty cycle. a 15C cont. and 30C burst rate maybe?

I wonder if there would be more interest in a 6000mah lifepo pack.

 

[morph999]

Then it sounds like they are way overpriced. Probably should be more around $40/pack.

 

[Truusje79]

I do think they improve a little after a few more test runs now, only slight though, when you throttle-up and ask for more amps, voltage drops are still present, and when doing it for a long time ( like 4 minutes @ full climbing hill ) voltage is under 14 volt per pack, throttle off is directly raising voltage very fast, now charged 8 times total.

These batteries aren't my biggest concern, but trying to write a review ( 2 star or "not satisfied". ) which got bounced TWICE is ridiculous of Hobbycity, although I did get my 5% discount bonus. ( read: STFU bonus )
One other person wrote a 1 star review and his comment got removed several days after mine, luckely we found each other on the forum, to b!tch some more about these packs but haven't heared of him for a while.

The other reviews were positive because they have a good run-time of 30 to 35 minutes on their RC cars / boats, but remember, these require a quick amp-peak of a few seconds and than low power for continuous runs AND 30 minute runtime is just 2C discharge average, this should be easy for the batteries. ( just as johnrobholmes mentioned )

Any suggestion on other cells ( headway, thundersky, ping ) please tell me about them, i'm looking for 50+ volt and 20 Ah for my KMX trike with long range needs......35 miles minimum.

 

[AussieJester]

Any suggestion on other cells ( headway, thundersky, ping ) please tell me about them, i'm looking for 50+ volt and 20 Ah for my KMX trike with long range needs......35 miles minimum.

Considered Lithium Polymer? Turnigy do a 22v 5000mah pack for ~$US55 alot of the fellas are using (myself included) along with GGoodrum's LVC parallel adapter boards (see my sig for link) you will get your 50v 20ah pack with very minimal voltage sag...

Best of luck anywayz..

KiM

 

[MitchJi]

Hi,

Any suggestion on other cells ( headway, thundersky, ping ) please tell me about them, i'm looking for 50+ volt and 20 Ah for my KMX trike with long range needs......35 miles minimum.

http://www.endless-sphere.com/forums/viewtopic.php?f=9&t=14832

2.5USD per Ah for 15Ah and 20Ah 30C LiFePO4 cells

More info:
http://endless-sphere.com/forums/viewtopic.php?f=14&t=15093
http://endless-sphere.com/forums/viewtopic.php?f=14&t=15408
http://endless-sphere.com/forums/viewtopic.php?f=14&t=14719

 

[Truusje79]

Yes aussieyester, I know the Turnigy Lipo's are excellent, I have a couple of them laying around for RC flying and use them also in my Makita batterydrill, it fits perfect snug into the slot where normally the NiCad would be.
Charged one maybe 100+ time and is still in super condition although I let it slip more than sometimes far below 3 volts per cell ( more like 1,6 ) it still pumps out around 1,3 mAh which it is rated for.

It crossed my mind using them for the E-bike, but I don't know if they hold up after let's say 300 cycles, for the 7 dollar I payed in discount for the 1.3Ah 3s they are tremendous value for money.....

And about the Turnigy LiFePo, i think they just have to wake up, these packs get somewhat better every time I use them, haven't tested it yet but they feel better and better, but 30C discharge, I'll never see them deliver this happily, not now ...... not in the future.

 

[AussieJester]

It crossed my mind using them for the E-bike, but I don't know if they hold up after let's say 300 cycles, for the 7 dollar I payed in discount for the 1.3Ah 3s they are tremendous value for money.....

Yes i think the 'jurys out' on that one i dont think anyone has been using them for 'years' to know the longitivity of them, suffic to say in e-bike use they aren't pushed anyware near the limits as when used in RC applications.

The prismatic A123s IMO are worth a look

KiM

 

[olaf-lampe]

@truusje79
I'm living around Aachen, just over the fence. If you are interested in selling the LiFe packs or you want me to do some comparing tests and cycles on my testbench, let me know. olaf-lampe [at]gmx dot de
By the way, my Clio Electrique is holding the lap record for electric cars in Zolder ( search cleanweek 2010 )

-Olaf

 

[pwbset]

And about the Turnigy LiFePo, i think they just have to wake up, these packs get somewhat better every time I use them

*bump* Are they still getting better? I'm looking around for battery solutions and 6 of these 3s2p might work for me if they can sustain 2kw+ for 15 minutes... like 4C. As bad as they are they can do 4C constant can't they?

 

[swbluto]

And about the Turnigy LiFePo, i think they just have to wake up, these packs get somewhat better every time I use them

*bump* Are they still getting better? I'm looking around for battery solutions and 6 of these 3s2p might work for me if they can sustain 2kw+ for 15 minutes... like 4C. As bad as they are they can do 4C constant can't they?

At 4C, it seems they would likely drop in voltage by (4/14c)*(3.3-2) = .37 volts so they'd likely have an output voltage in the 2.8 to 3.0 volt range per cell at 4C. It might even be higher depending on how much greater they've become.

Comparing this to the temperature performance of other packs at a similar voltage drop, it seems they "can do 4c constant".

Another way of looking at, if these are roughly half the capability a123 and a123's have a "continuous ability" of 10C (For longevity and all), then these are more like 5C continuous. For sure, they'd almost assuredly last a lot longer than your bosch packs.

 

[Truusje79]

And about the Turnigy LiFePo, i think they just have to wake up, these packs get somewhat better every time I use them

*bump* Are they still getting better? I'm looking around for battery solutions and 6 of these 3s2p might work for me if they can sustain 2kw+ for 15 minutes... like 4C. As bad as they are they can do 4C constant can't they?

Hi pwbset

First I would say no... now I say yes they will "do" 4C with room to spare...... did not test them anymore, it's winter here, not really bikeweather, but some thunderskies 20 Ah 12 volts are on their way so I'm selling these or keep them as Boost packs for longer range.

 

[StevenR]

replyt to liveforphysics

Spec.
Minimum Capacity: 4500mAh
Configuration: 6S2P / 19.8v / 12Cell
Constant Discharge: 30C
Peak Discharge (10sec): 40C
Pack Weight: 899g
Pack Size: 141 x 43 x 75mm
Charge Plug: JST-XH
Discharge plug: 4mm Bullet-connector


If I'm not mistaken, this is the best performance LiFePO4 in all battery critical aspects now?

Specific power
Specific volume to power
Specific energy
Specific volume to energy.


Does any other LiFePO4 offerings out there compare with this?

IMHO...
The list is not quite right or complete, depending how you look at it. The volume is not the variable of concern (within reason), it is mass - pounds(kg)/wh. At a certain capacity the power issues - instantaneous watts - are really moot. I get by nice on 80A continuous and I really need at least 20 aH to go the distance I need to go so the power output available at 20aH is really what I look at. Comparing to a Pingv3 48V20aH, Check my math:

Pingv3 48V20aH
At Least 1100wH as measured by CA - Still Pulling 40A, 2kW, so it is actually more
21 Pounds (<10kg) All Up - With BMS, Shrinkwrap, 2x80A Fuses and Fuse holders

Ping: 1100wh/10.0kg = 110wh/kg ***EDIT: 10000kg changed to 10.0 kg***
Turnigy: 19.8V*4.5Ah/.899kg = 99.1wh/kg

Ping: 10x6.5x4.75 inches = 25.4 x 16.5 x 12.1cm = 1100wh/5070cc = .217wh/cc
Turnigy: 14.1 x 4.3 x 7.5cm = 89.1wh/454cc= .196wh/cc

Pingv3: 1100wh/$900 = 1.22wh/$ delivered, with BMS and charger, ready to go
Turnigy: 89.1/70 = 1.27wh/$

The Turnigy wh figures are suspect in these calculations - real testing would be required and the additional hardware putting a pack together adds some weight too.
They are appearing to be 4C continuous instead of 30C. I can probably do that with the Pingv3 but it is rated and really delivers 3C...

 

[StevenR]

...continuing because the editor goes wacko after a certain number of lines...

I think the Ping v3 is still the leader in established non-vaporware. The new cells by the manufacturer we shall not name for sale here...
http://www.endless-sphere.com/forums/viewtopic.php?f=9&t=14832
...kick all the butt of everything right up to LiPo. The only factor that is of concern is wh/$ and the current handyman nature of the beast. The handyman issue apparently will soon go away (I'm handy, but I'm also too busy to build a battery). I will have to decide on the wh/$ conundrum when the pack price is determined.

 

[The Mighty Volt]

If I bought 4 of these, how would I arrange them in order to use with a hub motor?

Also, can they be charged using Turnigy balancers? I see they have that little thing for connecting {what's that called anyways, that ribbon of wires? }

 

[pwbset]

Pingv3: 1100wh/$900 = 1.22wh/$ delivered, with BMS and charger, ready to go
Turnigy: 89.1/70 = 1.27wh/$

Wouldn't it be:

Pingv3 $900/1100wh = $0.82/wh
Turnigy $70/89wh = $0.79/wh

And are you really seeing 1.1kwh out of your Ping 48v20ah? Strictly speaking math-wise/nominal voltage-wise 960wh is the obvious answer. Ping 3 huh... since they aren't on his website I can only assume you need to ask him through email for a pack like this?

 

[pwbset]

Strictly speaking math-wise/nominal voltage-wise 960wh is the obvious answer.

Wait that's not right either... Ping is 16s right? @ what like 3.2v nominal 3.65v "hot"??? Suppose I could just look it up.. head cold is makin' me lazy.

 

[swbluto]

You need to add shipping to Hobby-city price estimates. Those "$70 packs" are more like $85-$90 each with shipping (even when you buy in relative bulk).

 

[StevenR]

I got 1100wh measured by CA and have gotten there on several occasions. The CA power delivered wh matches the recharge wh measured by two different wattsup meters within about 2% (+ or -, mostly depending on when you call it charged - it will "charge" at 0.09A forever) every time. That should negate the nominal voltage question for the Ping. I used the nominal Turnigy voltage. I would consider that part of the equation to be the one that needs a better number. It may be a little better in some respects than the Ping if it delivers really well, which I would need a lot more info to believe, but it still has less energy density that I value most and is probably also more expensive per wh.

As far as Ping v3 availability - email Ping from the link on the website. He responds quickly and clearly. He will quote whatever weird thing you desire and he stands behind his product.

 

[morph999]

Any suggestion on other cells ( headway, thundersky, ping ) please tell me about them, i'm looking for 50+ volt and 20 Ah for my KMX trike with long range needs......35 miles minimum.

12v40AH Thundersky from evcomponents.com is probably the best buy of any lithium battery on the internet right now in my opinion.

36v40ah can be got for $530 (not including shipping). These Thundersky's have been improved since 2 or 3 years ago. I met someone on youtube who has been running Thunderskys in their car for a year with no problems.

 

[evblazer]

When I go over to elite power solutions for a 40ah pack with charger it shows $596 for a 24 volt and $836 for 36. Where are you finding them for so much less or is the charger what costs so much?
I'd have to shake the memories of the initial trials I know people went through with the thundersky's on the EVlist *shudder* but your price seems more reasonable then the ones I find.

 

[liveforphysics]

EVcomponents is a great shop with great guys. I met Dave personally at the track, and he is a true supporter of the EV revolution rather than just another guy trying to make a quick buck on batteries. :Thumbs up:

 

[evblazer]

When I go over to elite power solutions for a 40ah pack with charger it shows $596 for a 24 volt and $836 for 36. Where are you finding them for so much less or is the charger what costs so much?
I'd have to shake the memories of the initial trials I know people went through with the thundersky's on the EVlist *shudder* but your price seems more reasonable then the ones I find.

Elite Power Solutions marks up their inventory by 100%.

At EV Components we prefer thin margins and higher volume of sales. We take more of a Walmart approach to our pricing and make lithium cells more affordable for the DIY community.

James Morrison
http://www.evcomponents.com

Ok not sure how I missed the reference in there to evcomponents.com in the first post there I was just used to checking elitepower because they had the smaller (20ah) bike size.
I see single cells for $44 * 12 = $528 +10% = $580
Over at Elite power it is $836 with the charger, connectors and strapping for the same 12 cells. Probably not worth $256 but has to be something.
From a non cost perspective (former ev owner) I'd rather buy from evcomponents but the 40ah was too big for me. I'll have to do some research on the Thunder Sky - LiFeYPO4 - TS-LP20AHA.

Lots of choices but I guess it is better now then it used to be. Back then I could buy USBattery, Trojans or rebrands of either and it was a huge chore to get either anywhere.

 

[morph999]

I don't understand why elitepowersolutions marks up their 40AH cells so much, either but if you are just looking for 20AH cells, elitepowersolutions isn't a bad buy. $128 for 12v20AH pack so a 36v20AH would be about $384 without shipping. If you are looking for 40AH or greater, evcomponents.com is better. Actually, technically, evcomponents.com is better a better buy for 20AH cells too. They look like they come in different cases. Only reason I bought from elitepowersolutions was because I met someone on here who had bought from them and was happy with it and it was only $8 more per pack to buy from them.