Multistar LiPO C rating and realistic cont. discharge

Upperfoot · Feb 24, 2018

I have been scanning the forums and internet for some more information, and also asked HobbyKing's product specialist team to give me a bit more information about these packs.

The rating quoted is 10C so for a 10AH pack (https://hobbyking.com/en_us/multistar-high-capacity-6s-10000mah-multi-rotor-lipo-pack.html) it theoretically should output 100amps on paper, but as we know the C rating of packs is inflated to account for voltage sag, and not so much the actual discharge capabilities.

I get varying figures on the max C rating, such as;

10C - On paper, 20C peak discharge (10 seconds)
10C - HobbyKing Product Specialist - 15C peak discharge (10 seconds)
5C-10C - Varying values in forum replies

Can anyone shed some light on this at all with some real world experience with the packs?

brumbrum · Feb 24, 2018

There have been some tests done on the 10ah and 16ah multistar packs by forum member icecube57

I think the 10ah were good for 2.5C constant without any problems with heat or voltage sag.

The 16ah were suprisingly better at 4C

I have used 15 bricks of 4s 10ah multistars to make a 20s 30ah pack and they were really good. I used them upto 4C peaks and 2.5C constant and they never broke a sweat and gave a really good capacity and solid 3.7 to 3.8v per cell through out the discharge

I would say that above 4C they are going to get very warm

Upperfoot · Feb 24, 2018

brumbrum said:
There have been some tests done on the 10ah and 16ah multistar packs by forum member icecube57

I think the 10ah were good for 2.5C constant without any problems with heat or voltage sag.

The 16ah were suprisingly better at 4C

I have used 15 bricks of 4s 10ah multistars to make a 20s 30ah pack and they were really good. I used them upto 4C peaks and 2.5C constant and they never broke a sweat and gave a really good capacity and solid 3.7 to 3.8v per cell through out the discharge

I would say that above 4C they are going to get very warm

Thanks Brum,

Aww that's a shame, was going to build a 24s 60ah pack with 24 of the 6s 10ah for 24s6p, was hoping for around 250 amp constant and 550-600 peak for a Sevcon Gen4 size 6.

The multistars are the best bargain for cost per kwh hence why I was going to go with them, are there any others that are close in comparison but put out a higher discharge?

motomech · Feb 24, 2018

Nothing is on sale w/ the frequency and variety like the Multistar.
The Multistar is ok for my low powered systems, but before I switched to it, I was a Turnigy 20C fan. I still use a small aux. pack (12S/5 Ah) of the Turnigy that I swap back and forth w/ a MS pack of the same capacity and I can really feel the difference between the two. When the MS is about half discharged, I see 1 to 2 Volts of sag. No sag w/ the Turnigy till I'm right at the bottom.
Next to the MS, the Turnigy is most likely to go on sale, but they don't offer the big bricks that are so desirable w/ an ebike.

brumbrum · Feb 24, 2018

Upperfoot said:
brumbrum said:

There have been some tests done on the 10ah and 16ah multistar packs by forum member icecube57

I think the 10ah were good for 2.5C constant without any problems with heat or voltage sag.

The 16ah were suprisingly better at 4C

I have used 15 bricks of 4s 10ah multistars to make a 20s 30ah pack and they were really good. I used them upto 4C peaks and 2.5C constant and they never broke a sweat and gave a really good capacity and solid 3.7 to 3.8v per cell through out the discharge

I would say that above 4C they are going to get very warm

Click to expand...

Thanks Brum,

Aww that's a shame, was going to build a 24s 60ah pack with 24 of the 6s 10ah for 24s6p, was hoping for around 250 amp constant and 550-600 peak for a Sevcon Gen4 size 6.

The multistars are the best bargain for cost per kwh hence why I was going to go with them, are there any others that are close in comparison but put out a higher discharge?

When the MS are reduced in price they are a complete bargain for sure. You are asking about 4C constant from them which i reckon will be ok. Not sure how you will be building the pack but maybe a bit of ventilation/circulation of air maybe helpful

brumbrum · Feb 24, 2018

I,ve got to ask, what uses a constant 250 amps?

Upperfoot · Feb 24, 2018

brumbrum said:
I,ve got to ask, what uses a constant 250 amps?

Ordered a ME1616 from Voltsport, it's a 55KW peak water cooled motor from Motenergy, which I'm pairing with a Senior class Go Kart frame https://m.ebay.co.uk/itm/Octane-Wild-Kart-Rolling-Chassis-not-Tony-Kart-Alonso-Kosmic-Kart-/232622941037

A smaller motor would have been adequate, but go big or go home eh?

Upperfoot · Feb 25, 2018

motomech said:
Nothing is on sale w/ the frequency and variety like the Multistar.
The Multistar is ok for my low powered systems, but before I switched to it, I was a Turnigy 20C fan. I still use a small aux. pack (12S/5 Ah) of the Turnigy that I swap back and forth w/ a MS pack of the same capacity and I can really feel the difference between the two. When the MS is about half discharged, I see 1 to 2 Volts of sag. No sag w/ the Turnigy till I'm right at the bottom.
Next to the MS, the Turnigy is most likely to go on sale, but they don't offer the big bricks that are so desirable w/ an ebike.

That voltage sag is ridiculous, what was your max discharge looking like to get that voltage sag? If I didnt know that was the norm for these packs, I would have assumed it being a dud and RMA'd it without a second thought.

I wish the manufacturers would be a bit more honest with their specs, or at least give us the manufacturers baseline testing results to make up our own decision.

motomech · Feb 25, 2018

Lighten up, it was only a 5000 mAh pack.
There is plenty of discharge test results here, should you chose to take the time to look them up.
Search the posts of member icecube57.

Upperfoot · Feb 25, 2018

motomech said:
Lighten up, it was only a 5000 mAh pack.
There is plenty of discharge test results here, should you chose to take the time to look them up.
Search the posts of member icecube57.

A 2v sag for a pack designed for 4.2v fully charged at half discharge isn't acceptable by most standards, I'm unsure what you are insinuating, but thanks for the help I'll take a look.

motomech · Feb 25, 2018

For those of us w/ low-powered, assist-type ebikes, some sag from a very sm. pack is a fair trade for a smaller form factor, lighter weight and lower cost.
The responses here, correctly i believe, pointed out that the Multistar is not for you.
What I'm "insinuating" is, we don't need a rant that generalizes on how the industry markets it's products, which is a matter of opinion and irrelevant to this thread.

Upperfoot · Feb 25, 2018

motomech said:
For those of us w/ low-powered, assist-type ebikes, some sag from a very sm. pack is a fair trade for a smaller form factor, lighter weight and lower cost.
The responses here, correctly i believe, pointed out that the Multistar is not for you.
What I'm "insinuating" is, we don't need a rant that generalizes on how the industry markets it's products, which is a matter of opinion and irrelevant to this thread.

Thanks, Motomech, but I don't believe you're in a position to make a decision on whether my "rant" was warranted or not, and since the thread was started by me I don't see it as a problem, keep inflammatory comments to yourself next time rather than trying to cause trouble needlessly, if you have a problem talk to me over private message in future.

I've been looking at the Turnigy Heavy Duty packs and they look quite interesting (5ah, 60c cont.), though 30AH might be cutting it close for a 15 lap race for a kart.

motomech · Feb 25, 2018

Sorry if I came off snippy, but for many of here where the Multistar fits the application, the Multistars are heaven sent.
As I mentioned above, I am a big fan of Turnigy products, not only their LiPoly, but everything they offer. I started off w/ Zippy Flightmax and I have found the Turnigy will outlast and out-perform the comparable Zippy.
If you are in no hurry, put in some arlerts on the batteries you are interested in and eventually HK will put them on sale.

Upperfoot · Feb 25, 2018

motomech said:
Sorry if I came off snippy, but for many of here where the Multistar fits the application, the Multistars are heaven sent.
As I mentioned above, I am a big fan of Turnigy products, not only their LiPoly, but everything they offer. I started off w/ Zippy Flightmax and I have found the Turnigy will outlast and out-perform the comparable Zippy.
If you are in no hurry, put in some arlerts on the batteries you are interested in and eventually HK will put them on sale.

No problem! I'm sorry as well. I think I might take the plunge on the Turnigy brand, they have a 5.8AH 8s 25c at the moment for £35 which is a bargain! Though they are being discontinued so the longevity of the availability will be an issue.

Wish those Multistars had a little more oomph, but I'm probably asking too much from them considering they are already a bargain!

Multistar LiPO C rating and realistic cont. discharge

Upperfoot

100 W

brumbrum

100 kW

Upperfoot

100 W

motomech

10 MW

brumbrum

100 kW

brumbrum

100 kW

Upperfoot

100 W

Upperfoot

100 W

motomech

10 MW

Upperfoot

100 W

motomech

10 MW

Upperfoot

100 W

motomech

10 MW

Upperfoot

100 W

Similar threads