SamRich
100 W
Purchased the new 12C multistar last month during the HK sale: 2x 4S 16000mAh + 2x 6S 16000mAh ($330 shipped!)
I've built many packs with the 10C 10000mAh cells in the past, but they are now discontinued.
As other ES users have noted the 10C packs are really rated for 2-3C continuous and maybe 5C peak.
So I wanted to measure the IR of the 12C rated cells and see how they compare.
I also wanted to use the BT enabled ANT-BMS that I have used in a previous build using LTO since I really like the costumizability, the effective balancing and easy monitoring that it offers. https://www.endless-sphere.com/forums/viewtopic.php?f=14&t=91976
At $105 shipped the BMS is not cheap, but still not bad for 150A and up to 32S capable BMS. They are pretty bulky too. I figure it will outlive the cells and I'll be able to reuse for many packs to come. For an extra $15 you can get a display that needs to be mounted/cased in that provides cell data, speed, Ah etc.. which is better than Batt-man and a bit different than a CA - but a good alternative.
Wiring the BMS and soldering the packs together was pretty straight forward
I got the optional display to test. You can power it off the stack voltage, which was not clear in the instruction - since it used to require a 6-20V standalone power supply.
Connected to it via bluetooth with the VBMS app on my phone. All cells were well balanced after one charge.
Here's the finished pack - not the prettiest, but I wanted to keep it into two modules for packing in a pannier or triangle bags. This tethered design allows me some flexibility when fitting it in non-square spaces.
BTW these MS batteries are actually 2P packs inside so two 8Ah cells in parallel.
I did a quick test on my bike at 45A and saw about 2.1V of sag at 20S- not bad!
That's roughly 47 mOhms for the whole pack or 2.3 mOhms per 16Ah cell or 4.7 mOhms per 8Ah cell.
I remember measuring closer to 5-10 mOhms for a 10Ah for the older 10C rated cells (were not new when tested though).
Does anyone have measurements to share? either for the new 12C or old 10C Multistars?
I'll update this post as I collect more test data:
45A Test:
Dec 12th 2018 - 3 Charges: 47 mOhms IR
I've built many packs with the 10C 10000mAh cells in the past, but they are now discontinued.
As other ES users have noted the 10C packs are really rated for 2-3C continuous and maybe 5C peak.
So I wanted to measure the IR of the 12C rated cells and see how they compare.
I also wanted to use the BT enabled ANT-BMS that I have used in a previous build using LTO since I really like the costumizability, the effective balancing and easy monitoring that it offers. https://www.endless-sphere.com/forums/viewtopic.php?f=14&t=91976
At $105 shipped the BMS is not cheap, but still not bad for 150A and up to 32S capable BMS. They are pretty bulky too. I figure it will outlive the cells and I'll be able to reuse for many packs to come. For an extra $15 you can get a display that needs to be mounted/cased in that provides cell data, speed, Ah etc.. which is better than Batt-man and a bit different than a CA - but a good alternative.
Wiring the BMS and soldering the packs together was pretty straight forward
I got the optional display to test. You can power it off the stack voltage, which was not clear in the instruction - since it used to require a 6-20V standalone power supply.
Connected to it via bluetooth with the VBMS app on my phone. All cells were well balanced after one charge.
Here's the finished pack - not the prettiest, but I wanted to keep it into two modules for packing in a pannier or triangle bags. This tethered design allows me some flexibility when fitting it in non-square spaces.
BTW these MS batteries are actually 2P packs inside so two 8Ah cells in parallel.
I did a quick test on my bike at 45A and saw about 2.1V of sag at 20S- not bad!
That's roughly 47 mOhms for the whole pack or 2.3 mOhms per 16Ah cell or 4.7 mOhms per 8Ah cell.
I remember measuring closer to 5-10 mOhms for a 10Ah for the older 10C rated cells (were not new when tested though).
Does anyone have measurements to share? either for the new 12C or old 10C Multistars?
I'll update this post as I collect more test data:
45A Test:
Dec 12th 2018 - 3 Charges: 47 mOhms IR
