Turnigy Multistar - lightweight 10C cells
- Thread starter miuan
- Start date
dnmun said:
Even if the cell does not have a high self-discharge, the voltage difference means something else is different about that one cell compared to the rest. Why would cells manufactured at the same time, exhibit different property compared to the rest. It's something we all outliers in statistics. This usually means something is way wrong with that one cell. Why take the risk? Sure it might be good for the next 100 cycles or so, but then it will rapidly degrade. You don't see the bad cells until you cycle them up to around 100 times for lipo. Other chemistry will take more cycles. Consider it lucky that one cell have shown itself before you need to cycle them at all to find the bad cells.
From experience, I can assure you the weak cell will give them problems down the road. Maybe not within the first 100 cycles, but for sure after more cycles. Hey if you are ok with those type of quality control, then you are welcome to buy my HK lipo from me at the same price HK is selling me. I have a few that exhibit this behavior. They arrived weak compared to the rest of the pack. They all ended up lasting around 100 cycles and total crap out later on. I could not get them to charge up to 4.15V anymore. The other cells would be fine. The charger would give up and once I disconnect them, they would fall right down to 4V while the rest is at 4.2V. It later had high internal resistance.
My point is there is no company I know of that will sell you cells from all the same batch with that voltage difference. They usually consider those defective and either cut the defective cell out or throw the whole pack away.
dnmun
1 PW
you do not know what voltage it was charged to in the formation charge. to assume each pouch is charged to the same state of charge is simply that, an assumption. it does not in any way indicate that there is a high rate of self discharge.
that has to be established by testing the cell. there is no evidence presented that he has ever tested this pouch to establish the claim he has made.
then to top it off he says that ping sold him a defective battery too.
again, with no evidence, just his statement to trash the seller's reputation for the google bot.
a 5,000 mAh pouch with 500mA of self discharge would totally discharge to 0.00000V in less than 7 hours with a formation charge to 70% SOC. it is as though there is no concept or understanding of the incredible misinterpretation of the fact that one of his pouches is not identical to the others.
imo the charge lost could just as easily occurred when the pouch was accidentally shorted while it was being soldered. the resting voltage appears to be exactly what i have seen in that situation when it has occurred to me.
that has to be established by testing the cell. there is no evidence presented that he has ever tested this pouch to establish the claim he has made.
then to top it off he says that ping sold him a defective battery too.
again, with no evidence, just his statement to trash the seller's reputation for the google bot.
a 5,000 mAh pouch with 500mA of self discharge would totally discharge to 0.00000V in less than 7 hours with a formation charge to 70% SOC. it is as though there is no concept or understanding of the incredible misinterpretation of the fact that one of his pouches is not identical to the others.
imo the charge lost could just as easily occurred when the pouch was accidentally shorted while it was being soldered. the resting voltage appears to be exactly what i have seen in that situation when it has occurred to me.
Farfle
100 kW
dnmun said:
Typically we junk anything that isn't within .05 of a volt out of package. Most Turnigy cells are around 3.85v when we get them, seeing a majority of the pack at 3.92 is odd, but the one thats slightly lower is barely outside of what we consider acceptable at the bike shop. Like with all hobby lipo, order one more pack, Junk the bad one. returns at HK are a waste of time.
icecube57
10 MW
All of my packs of the multi star came at 3.89 to 3.92. They were really fresh or the stuff we get from HK has been sitting around for a minute.
Farfle
100 kW
icecube57 said:
Also possibly charged to a different point before storage/shipping. Hard to know without visiting the factory
dnmun said:
He quite clearly meant 500mAh, based on the difference in terminal voltage indicating SOC.
You are making just as much of an assumption by saying the formation charge isn't to the same SOC for all cells. It's more logical to assume the formation charge process is somewhat controlled and doesn't charge different cells in a random manner.
HK lipo quality is spotty at best. A pack arriving with one cell down compared to the others is unlikely to be good news.
(I HAVE NO ELECTRONIC TRAINING OR QUALIFICATIONS, ANY INFO IS JUST AVERAGE END USER OBSERVATIONS, I did not come here to state my pack to be majorly faulty but came here for opinions after the HK advisor said it might be duff)
Sorry bit busy but yes it took over 500mah(I keep getting ma's and mah's mixed up due to a memory problem after brain damage) to get it back in line with the other cells. I bought 2 new packs to add to it anyway so I am not running 4c (40a controller+mac 10t). My concern was these are brand new cells that have had no time to sit on shelves and it has still arrived with one out of 12 cells lower than the rest just like my ping.
The ping battery had a cell number 7 (near the positive end of the pack) constantly self discharge from day one. Only 100mah a week or something but every day when I come to my pack that cell was down to nominal voltage even 24hrs after charging. All other cells stayed at 3.58v for weeks. The standard bms took up to 24hrs hours to correct it. So I just gave up, fitted a balance port and charged each cell individually down the second set of fat balance wires I had fitted. This cell drained itself with no bms attached so by elimination it cant be anything else.
Anyway the reason I thought to let people know not to rush in too fast was that I seemed to have 1 iffy pack out of 2 (50%). I didnt mean forever just until someone did some tests and gained some proper data. Some people like to be early adopters some like to wait for tests. I would have waited a bit longer if someone said they had been getting uneven cell voltages on the very first packs supplied.
I can now confirm I have 4 packs and all the other cells are at 3.92v exactly. Il let you know in 6 months when or if it flakes out. Im loving the size and weight reduction from my last set up.
*this guy thinks .10v difference shows a possible problem so probably panicked as I always get duff stuff online
http://www.tjinguytech.com/charging-how-tos/lipo-issues
pics next to a 48v 20ah lifepo4
Sorry bit busy but yes it took over 500mah(I keep getting ma's and mah's mixed up due to a memory problem after brain damage) to get it back in line with the other cells. I bought 2 new packs to add to it anyway so I am not running 4c (40a controller+mac 10t). My concern was these are brand new cells that have had no time to sit on shelves and it has still arrived with one out of 12 cells lower than the rest just like my ping.
The ping battery had a cell number 7 (near the positive end of the pack) constantly self discharge from day one. Only 100mah a week or something but every day when I come to my pack that cell was down to nominal voltage even 24hrs after charging. All other cells stayed at 3.58v for weeks. The standard bms took up to 24hrs hours to correct it. So I just gave up, fitted a balance port and charged each cell individually down the second set of fat balance wires I had fitted. This cell drained itself with no bms attached so by elimination it cant be anything else.
Anyway the reason I thought to let people know not to rush in too fast was that I seemed to have 1 iffy pack out of 2 (50%). I didnt mean forever just until someone did some tests and gained some proper data. Some people like to be early adopters some like to wait for tests. I would have waited a bit longer if someone said they had been getting uneven cell voltages on the very first packs supplied.
I can now confirm I have 4 packs and all the other cells are at 3.92v exactly. Il let you know in 6 months when or if it flakes out. Im loving the size and weight reduction from my last set up.
*this guy thinks .10v difference shows a possible problem so probably panicked as I always get duff stuff online
http://www.tjinguytech.com/charging-how-tos/lipo-issues
pics next to a 48v 20ah lifepo4
crezzy2k1
1 W
so icecube how the packs holding up so far, i'm looking at these for a future project.
dnmun
1 PW
why is everyone so ignorant of the fact that he did not do any test to establish his claim that there is huge self discharge? then he made this claim that there was. that was what i pointed to. then all this touristo crap about how if it is not within 5mV then scrap it.
with that kinda money that you can just throw away a lipo pack i wonder why you even are buying from hobby king to begin with. who has that much money anyway? just buying a few watt hours almost breaks me.
the rest of us have to actually measure the self discharge rates of individual channels on a built 21S 44Ah pack to find the culprits. it requires testing and evaluation of the results to determine the leakers but those of us without this huge wad of cash to throw away have to do it since we pay our own way.
i am more than little annoyed since i have just had to spend two days finding mine and he doesn't have to do a thing but make some unsubstantiated claim, which is par for the sphere now. there used to be a time when people knew what they were talking about here.
with that kinda money that you can just throw away a lipo pack i wonder why you even are buying from hobby king to begin with. who has that much money anyway? just buying a few watt hours almost breaks me.
the rest of us have to actually measure the self discharge rates of individual channels on a built 21S 44Ah pack to find the culprits. it requires testing and evaluation of the results to determine the leakers but those of us without this huge wad of cash to throw away have to do it since we pay our own way.
i am more than little annoyed since i have just had to spend two days finding mine and he doesn't have to do a thing but make some unsubstantiated claim, which is par for the sphere now. there used to be a time when people knew what they were talking about here.
icecube57
10 MW
Here is a 25A discharge curve of the 10C Multistar pack.
So far from what I see is the packs seem to be performing well. They are over delivering on capacity by a good margin. 10.2-10.7AH. There isnt that much of a loss between different discharge rates. On one pack I discharged @5A and it delivered 10.430AH on a 25A discharge on the same pack it only decreased by 65mah to 10.365AH. I would say this is in the margin of error.
These packs are very square compared to the 6s 8AH Zippys which appeared to be round and bloated but firm.
I would say its ok to take 25A from these packs in a 1P. I would run them in atleast 2p for high discharge applications.
So far from what I see is the packs seem to be performing well. They are over delivering on capacity by a good margin. 10.2-10.7AH. There isnt that much of a loss between different discharge rates. On one pack I discharged @5A and it delivered 10.430AH on a 25A discharge on the same pack it only decreased by 65mah to 10.365AH. I would say this is in the margin of error.
These packs are very square compared to the 6s 8AH Zippys which appeared to be round and bloated but firm.
I would say its ok to take 25A from these packs in a 1P. I would run them in atleast 2p for high discharge applications.
Attachments
parabellum
1 MW
bionicdan said:
I wonder how manufacturer matches cells in to packs and how they know exact capacity of each cell printed on those small white stickers on every one. I would be very careful with all "this guy thinks".
teslanv
1 MW
I threw together a quick analysis spreadsheet of the Multistar Battery vs. other Hobbyking (as well as Ping & EM3EV NCM) batteries.
The MultiStar is the clear winner in terns of watt-hour/weight & watt-hours/volume, and second only to the 4S Hard case packs in purchase price/Watt-Hour.
The MultiStar is the clear winner in terns of watt-hour/weight & watt-hours/volume, and second only to the 4S Hard case packs in purchase price/Watt-Hour.
crezzy2k1
1 W
I'm thinking these packs will be excellent for a cross state trip i'm planning on doing next year. Thanks for the information guys 
danielrlee
10 kW
Assuming they hold up in terms of charge cycles, these packs are starting to look like a great option for EV use. I am currently able to comfortably fit 12 4S hardcase packs into a triangle bag (20Ah @ 12S). I reckon I might be able to fit 30Ah @ 12S of these high capacity packs into the same bag and at only an increase of 25% in relative cost.
icecube57
10 MW
If you have the right frame with a large triangle you can shove 10 of these in a Falcon EV Frame Bag. Which means 12s 50AH I have 12s 40Ah in mine now for my BBS02 29er Build.
Damn 16000mah 6s now, wish I had seen these first but there is a glitch in the site meaning they dont show to people in the uk list (even though they are uk stock). Probably why they are the only ones left lol. Works out about £5 per ah instead of £6 per ah on the 10.000ah ones with the weight of a mars bar as penalty per pack.
Got some on the way anyway, nothing wrong with having some options before I head out on a ride
http://www.hobbyking.com/hobbyking/store/__66310__Multistar_High_Capacity_6S_16000mAh_Multi_Rotor_Lipo_Pack_EU_Warehouse_.html
Ps my pack that came with a low cell still seems to have very minor variances despite extensive balancing but its working ok so far. One of the cells, that wasnt actually the low one on delivery, hit 3.31v when the others where at 3.55v. The pair I bought to parallel/support the pack are perfect on charge and discharge.
Got some on the way anyway, nothing wrong with having some options before I head out on a ride
http://www.hobbyking.com/hobbyking/store/__66310__Multistar_High_Capacity_6S_16000mAh_Multi_Rotor_Lipo_Pack_EU_Warehouse_.html
Ps my pack that came with a low cell still seems to have very minor variances despite extensive balancing but its working ok so far. One of the cells, that wasnt actually the low one on delivery, hit 3.31v when the others where at 3.55v. The pair I bought to parallel/support the pack are perfect on charge and discharge.
Hillhater
100 TW
I wonder why there are no 5S Multistar packs ?
Also very frustrating in that no amount of search options, country changes, etc will bring up the high capacity Multistar packs on the HK site ? ....nothing above a 6S, 8000mAhr shows up on the site, and a "global" search only shows a 4S, 5200mAhr as the largest ?
Only the links posted here work for those 10 + Ahr packs.??
Also very frustrating in that no amount of search options, country changes, etc will bring up the high capacity Multistar packs on the HK site ? ....nothing above a 6S, 8000mAhr shows up on the site, and a "global" search only shows a 4S, 5200mAhr as the largest ?
Only the links posted here work for those 10 + Ahr packs.??
Russell
1 MW
Hillhater said:
I have no problem finding the packs using their LiPo Finder;
http://www.hobbyking.com/hobbyking/store/lithium_polymer_battery_configuration.asp?cap=4&con=5&location=INT
-R
Hillhater
100 TW
Russell said:
What do you enter in the finder table ?
I checked the 6000+ mAhr box, asked for 10 C, and 6S
..and i get 8ahr Flightmax 6S or 8Ahr 6S nanotech..??
..no suggestion of anything else !
made_in_the_alps_legacy
10 kW
seems to be related to the selected warehouse :wink:
Russell
1 MW
Hillhater said:
Select warehouse
Check the 6000+ box
Run the Discharge(c) slider to 10C
Check the Config you want (only 4S,6S available)
For 6S I get:
Nothing at International
6600 and 8000 at Australian warehouse
6600,8000 and 10000 at USA West
6600,8000 and 10000 at UK (all out of stock)
6600,8000,10000 and 16000 at European (16Ah out of stock)
6600,8000 and 10000 at USA East
Don't know any reason you wouldn't get the same results unless you're not selecting a WAREHOUSE.
-R
liveforphysics
100 TW
When the cells used in an RC pack complete final QC after finishing final-formation, they are charged to +-1mV of the same voltage.
When you see a low one, it is likely it has an internal self-discharge issue that will lead to gassing and failure. However, a more through test of this self-discharge behavior would include charging them all to 4.2v, and letting them all sit together in a warm-ish (35degC?) place for a week or so, then measuring each cell again and compare them with there previous voltages to look for drop.
When you see a low one, it is likely it has an internal self-discharge issue that will lead to gassing and failure. However, a more through test of this self-discharge behavior would include charging them all to 4.2v, and letting them all sit together in a warm-ish (35degC?) place for a week or so, then measuring each cell again and compare them with there previous voltages to look for drop.
