Turnigy Multistar - lightweight 10C cells

[mvly]

The capacity between 4.2 and 4.1 is about 800-900mah. So thats what you loose by under charging the battery.

Wow! For a 10Ah pack that is 90%. Kind of hard to give up that 10% capacity just for the sake of longevity. But again it all depends on what your usage is. Most people running lipo usually buy 110% to 120% capacity anyways knowing the last 10-20% is required to keep lipo pack running for a long time.

 

[Punx0r]

Indeed.

Good work Mr. Icecube - disappointing that these packs are realistically only 2.5C continuous, but hardly surprising they fall short of the advertised C-rate...

 

[Russell]

I just finished my test. First test was at 10A and i got 10185mah on the discharge and the cell got up to 42C or 107F. The second test was 20A and I got 10132mah and the pack got up to 49C or 120F. So in conclusion 2.5C is probably your stopping limit for continuous use.

I noticed my lithium batteries tend to get their warmest when I push them past about 70% DOD. Since most folks don't do full discharges maybe you could re-run your tests taking temperature measurements along the way to see if there's a point where the temps start rising faster.

Keep up the good work.

BTW, I took my first ride with my Multistar 16000's today.

-R

 

[icecube57]

The pack is fine up to about 8AH then the temp starts rising super fast. Regardless of the C rate discharged. Ive only discharged at up to 5C. No need to go any higher and abuse a pack that cant deliver at a decent voltage. These pack have their place if you want range without a penalty of the weight and space then these are great. Especially when ran at 2P or more. Im running 2s 4P with a BBS02with a 25-30A controller. My setup is overkill and well within the revised discharge specs. I have a friends that has my 5000w GM Pie setup thats running 3s3p and its properly sized for his setup. Alot of you are looking at the Weight the C rating and Capacity and think cool I can have a grocery getter. Thats not the case. Multistar..Multi....Atleast 2P and you are golden for setups over 1000w.

 

[kudos]

Indeed.

Good work Mr. Icecube - disappointing that these packs are realistically only 2.5C continuous, but hardly surprising they fall short of the advertised C-rate...

So can someone please confirm when you say 2.5C continuous.

For the 16Ah pack that would be 16 x 2.5 = 40A right?

Kudos

 

[icecube57]

Indeed.

Good work Mr. Icecube - disappointing that these packs are realistically only 2.5C continuous, but hardly surprising they fall short of the advertised C-rate...

So can someone please confirm when you say 2.5C continuous.

For the 16Ah pack that would be 16 x 2.5 = 40A right?

Kudos

Ive tested the 10AH pack. I would assume the 16Ah is the same formulation so it should scale up without issue in theory. Just remember you might start flirtin with LVC a little bit earlier vs real lipo. My 2.5C rating is also based on a full discharge and looking at the temperature of the pack. It reached what I would call a max temp for lipo which is around 45-50C when discharged constant at 25A. Any higher discharge its a hot potato and you risk bloating.

 

[The Mighty Volt]

Okay, extrapolating IceCubes 2.5c rule for a 16Ah pack, that's 40amps. Extrapolating for the temperature limit, that would be 12.8ah before you start to overheat.

I reckon these are good value for money if you match them to your ride.

No point putting 72v 16ah of these on a cromotor in a 26" wheel.

But they might work on a MAC Motor or a Pie in a 20".

Take 4 of them, 2s2p and that would give you 44v and 32Ah, so you can double your values, or multiply them by 1.5 to stay safe.

44v for my 20" 6T MAC..and 32Ah...these would sound a good cheap viable fuel.

 

[Ohbse]

Could somebody that has already purchased a 4s 16ah battery please provide some actually accurate measurements?

Specifically I am interested in the length, is this actually 173mm including the space required for the leads? Or is it slightly more than this in the real world?

My application is potentially 20s 32ah of the 4s 16ah packs jammed into a pelican 1300 on my fork. This should be about 2,368WH, probably 2.2kwh usable. This is the absolute most that I can fit into a pelican, even bettering the 18650 power cells in a 20s12p configuration while still providing more than enough punch for my cromotor/max-e setup. I can't forsee using more than ~60amps continuous as this is already cruising at 70+km/h. Peaks of 120amps will be peaking at <4c so cells should not be too stressed (and 120amps for 5 seconds is very fast indeed)

Problem is the fit is *very* tight. a 1mm discrepency between the hobbyking dimensions and reality could mean this will never work, I really need to know in advance... I'm already going to have a very tough time with packaging the wiring, especially BMS.

 

[icecube57]

One thing i must say about this battery is I think had a 90% DOD on my pack and I still had 3.7v a cell and it was no deviation in balance. I have a 2s 4P 44v 40AH battery.

 

[Offroader]

One thing i must say about this battery is I think had a 90% DOD on my pack and I still had 3.7v a cell and it was no deviation in balance. I have a 2s 4P 44v 40AH battery.

icecube, I don't understand when you say 80% DOD and the cells start heating up fast. Wouldn't it be more accurate to say a voltage to go under than a 80% dod? LIke they start heating up below 3.7 volts for example.

The specs that hobby king has for these multistars are dead accurate as other measured them and reported their findings. You can go with the specs listed on hobby kings website.

 

[striker54]

Could somebody that has already purchased a 4s 16ah battery please provide some actually accurate measurements?

Specifically I am interested in the length, is this actually 173mm including the space required for the leads? Or is it slightly more than this in the real world?

I have the 4S and the 6S. They probably won't fit. I've measured them and with the leads the lenght is 186mm without pressure:
View attachment 1

And with hard pressure i achive 182mm:


The other two dimensions are correct.

Regards.

 

[icecube57]

The way these packs are made I wouldnt apply pressure to compress them in the manner you used to shorten them.

 

[icecube57]

One thing i must say about this battery is I think had a 90% DOD on my pack and I still had 3.7v a cell and it was no deviation in balance. I have a 2s 4P 44v 40AH battery.

icecube, I don't understand when you say 80% DOD and the cells start heating up fast. Wouldn't it be more accurate to say a voltage to go under than a 80% dod? LIke they start heating up below 3.7 volts for example.

The specs that hobby king has for these multistars are dead accurate as other measured them and reported their findings. You can go with the specs listed on hobby kings website.

The specs maybe accurate for burst and only if the SOC is high.

I have measured them and reported my findings. There are a few charts here on ES of me doing discharge curves. I have stated how they perform. How they are generous on capacity. I just mention how well the pack stayed balanced even at 90% DOD

Ive sat here and bench tested multistars a 25A the temperature stays solid and respectable up to about 80% DOD (or 20% left in the pack) or (8AH Discharged out of 10) then the pack temps starts to rocket due to the increased IR. The IR is high on these packs so a 25A load at a given voltage would suck and probably at LVC if I tried to give under load voltages. With pack IR being high it is possible for certain systems to leave alot of capacity left on the table unless you reduce the amps.

But I tell you right now the 3.7v resting we know for normal lipo as being the nominal voltage for 50% is different for these multistars. Its mor like 90-95%. You can run them at whatever C rate you want to its up to you but I found that the performance past 20-25A sucks in terms of voltage sag and whats acceptable for ebike use. Ive tested them at 5C constant for the entire discharge and they arent able to cope with that. I would run these packs in atleast a 2P configuration to get decent performance.

With most of hobby king stuff you have to run them at 1/4 of their advertised C rate for constant draw and this is no exception

 

[Offroader]

Could somebody that has already purchased a 4s 16ah battery please provide some actually accurate measurements?

Specifically I am interested in the length, is this actually 173mm including the space required for the leads? Or is it slightly more than this in the real world?

I have the 4S and the 6S. They probably won't fit. I've measured them and with the leads the lenght is 186mm without pressure:
View attachment 1

And with hard pressure i achive 182mm:


The other two dimensions are correct.

Regards.

Could you measure the other ways striker54? The Length & Width

Yeah the height is always going to be different because of the way they wrap these packs. Plus you may have to leave space for the wires.

 

[liveforphysics]

The way these packs are made I wouldnt apply pressure to compress them in the manner you used to shorten them.

+1

When I started working with pouch cells, I handled them like they were little bricks.

After 7 years of working with pouch cells on a daily basis, I don't even like human hands to contact them anymore, and ONLY through delicately through the Z-axis if they are going to be handled.

 

[striker54]

Could you measure the other ways striker54? The Length & Width

4S:
74.3mm x 46.6mm


6S
74.3mm x 69.5mm

 

[icecube57]

Getting measurements like this is pointless cause Ive had packs that were skewed. The odds on you getting perfectly square pack that are nominally accurate to the spec given are slim and nil. You should underestimate the size of your enclosure the packs will be in instead of wedging and packing it in. Seems like you are trying to fit something thats going to be really tight but it might fit. The only im concerned about is pack chaffing in tight spaces. i will take padding in my enclosure vs a tight fit any day.

 

[dnmun]

i keep telling people to remove the shrink wrap as soon as they receive the lipo. take the packs apart and build the battery using the pouches as cells in a battery just as li ping did with his lifepo4 packs and then use hardboard end plates and then wrap them with duct tape to keep them in compression as they swell with age.

the pelican boxes are not orthogonal either. the top is wider than the bottom so the pouches will be distorted as they swell over time and i feel that will shorten the cycle life just like leaving the shrink wrap on the pouches.

 

[Offroader]

Thanks striker,

Yeah the outer cells on the packs almost always seem to go first. I've had to repair many of them.

But I never really padded my batteries down properly. I usually have very little room and am trying to get as many batteries in as possible. I think the key is to use that thick AC foam for padding and make sure the cells aren't pushed into anything not flat, like a round bike tube frame.

 

[icecube57]

i keep telling people to remove the shrink wrap as soon as they receive the lipo. take the packs apart and build the battery using the pouches as cells in a battery just as li ping did with his lifepo4 packs and then use hardboard end plates and then wrap them with duct tape to keep them in compression as they swell with age.

the pelican boxes are not orthogonal either. the top is wider than the bottom so the pouches will be distorted as they swell over time and i feel that will shorten the cycle life just like leaving the shrink wrap on the pouches.

I ended up wrapping mine in Frog Tape Masking Tape for easy removal if I need to later. Then Filament Tape to maintain tight compression. Way better than the heat shrink could ever do and then Gorilla Tape to add a bit more of mechanical protection. I line the bottom of my battery bag with memory foam.

 

[The Mighty Volt]

I know this might be harsh, and premature, but...in a word, yes or no, for these batteries??? Thanks.

 

[dnmun]

IC, i avoid allowing the tape to wrap around the corners of the pouches. i feel that the squeezing of the edges by the tape and shrink wrap causes the electrode/separator sandwich inside to be deformed along the edges and that is damaging to them as the electrode/separator sandwich gets squeezed tighter and tighter until the cathodic mixture is displaced or the electrodes push all the way through the separator and short.

so i use the hardboard plates on the ends to keep the tape off of the pouches.

 

[Offroader]

I know this might be harsh, and premature, but...in a word, yes or no, for these batteries??? Thanks.

Based on what was tested and what icecube says, it depends on your current draw and how big a pack you can fit.

I say they are the best deal around and will surely be using them when I need to replace my batteries. But I also build very large packs, like 2700 watt hours and expect to build a 32 amp hour pack with these. At 22s I'll be drawing only around 70 battery amps so just over 2C .

My battery pack weighs like 40 lbs on my bike, using these would knock the weight down to 32 lbs and also give me 20% more room in my battery compartment. Maybe I'll build an even bigger pack!

These batteries also cost less than anything I can find on the market if you purchase the larger size packs like the 6s 16,000MAH.

Definite Win in my book.

 

[Sunder]

Hey guys,

This is a really dumb question, but I wanted to ask so I don't waste my time and parts...

Story is that I bought the Multistar 6S 16Ah battery, but I left them at work, as I didn't have enough luggage space to carry them home over the weekend. I don't get back to the office until Monday, but I want to ride to the office with a full set of working harnesses, so I can charge, balance and ride off with the new batteries from the office.

I've been looking at the photos others have posted, and I'm 90% sure the XT90s are the socket side on the battery. Makes sense as it's safer. But none of the photos are full frontal on the XT90 fitting. I don't want to make up the parallel and serial harnesses to find out I'm wrong.

Can anyone confirm that the battery has the socket side, and the harnesses should have the pin side?

Thanks.

 

[teslanv]

Here is what the charger/controller side would look like:

http://www.hobbyking.com/hobbyking/store/__25660__XT90_to_Banana_Plug_Charge_Lead_Adapter.html