Lipo with Integrated BMS

n2mb

100 W
Joined
May 25, 2018
Messages
255
Has anyone tried these packs or have any more details on the integrated BMS? It's not cheap, but if it includes balancing and protection, it might be an easy way to get high current batteries onto an oddly shaped full suspension mountain bike. Just stick three in series and use a bulk charger, like the cycle satiatior?

https://www.genstattu.com/tattu-plus-12000mah-22-2v-15c-6s1p-lipo-smart-battery-pack-with-as150-xt150-plug.html
https://www.amazon.com/Tattu-Smart-Battery-12000mAh-Integrated/dp/B01LL29BGE/
 
Why would you buy a hobbyking bomb-in-a-bag with some plastic?

Its way too expensive and dont have any advantage to regular 18650 pack.
Its way easyer to make a odd shape with regular cells then with a few really expensive bricks.
 
Because it's really hard to find an 18 650 pack that fits a full suspension mountain bike that has high enough voltage (60v and up) and can deliver a lot of current (70a and up).
 
n2mb said:
Because it's really hard to find an 18 650 pack that fits a full suspension mountain bike that has high enough voltage (60v and up) and can deliver a lot of current (70a and up).

Try to move to 21700 cells. For example Samsung 40T offers 4000mAh capacity and 35A continuous discharge rate or LG M50 at 5000mAh/10A.
And your balls will be in safety, which is the most important advantage :)
 
Does anyone make a pack with 21700 cells? I just want to buy a pack. I don't have time to build one. I don't really even have time to build an eBike, but I can't buy one with the performance I want... I would have just bought the Sur Ron, if I could get one with a damn VIN and register it as a moped!
 
My main pack is 4) Multistar 6S/10,000mAh bricks configured 2S/2P for a 12S(46.5V nom.)/20,000mAh pack. They are currently on sale @ HK for $75 delivered, making my total cost $300.
To duplicate w/ these "smart" bricks, I would need 4 of these;
https://www.genstattu.com/tattu-plus-10000mah-22-2v-25c-6s1p-lipo-smart-battery-pack-with-as150-xt150-plug.html
So that would be $844 plus shipping!
No thanks, for a savings of $544/plus shipping, I can check my bricks w/ a Battery Medic.
And this doesn't even take into consideration their greater size and weight.
What is needed for battery control and monitoring for a drone and an Ebike are two completely different things. The way I see it, the biggest advantage to these batteries is the built-in LVC. Drone drivers need to use some sort of audiable alarm, while most ebikes have a LVC built into the controller, so that feature is negated.
Probably the biggest downside of using LiPoly on an ebike is the time required to do a 2-stage charging process(storage Voltage/top charge Voltage)and these batteries still require this 2-stage process, so no advantage there either.
 
motomech said:
The way I see it, the biggest advantage to these batteries is the built-in LVC. Drone drivers need to use some sort of audiable alarm, while most ebikes have a LVC built into the controller, so that feature is negated.
Probably the biggest downside of using LiPoly on an ebike is the time required to do a 2-stage charging process(storage Voltage/top charge Voltage)and these batteries still require this 2-stage process, so no advantage there either.

I don't think these packs have low voltage cut off or any cutoff. It would be too bulky to integrate enough transistors in parallel to be able to actually cut off the power and still be able to pass 100s of amps. But, that is ok since as you mentioned, most controllers have a low voltage cut off.

I think the huge advantage here is if they have a functional balancing circuit! That would allow bulk charging of the series string of LiPos on the bike using a standard ebike charger. I would vastly prefer that then having to take the batteries off the bike every day when commuting...

They mention balance charging, but it's not quite clear if / how it works.


Alternatively, it would be great if someone made a plug and play BMS for Lipo packs. Just plug in three XT-90s and the balance leads and you get out an XT-90 with overcurrent protection and another XT-60 for charging...
 
motomech said:
My main pack is 4) Multistar 6S/10,000mAh bricks configured 2S/2P for a 12S(46.5V nom.)/20,000mAh pack. They are currently on sale @ HK for $75 delivered, making my total cost $300.

You are right, though, those 10 ah packs are really cheap! I'd been looking at the 16 Ah and 20 aH ones....

I'm guessing the 10C rating is optimistic, though... Any thoughts on running 3 of them in series and pulling 70A/80A peak from them? I really want 60+ volts to get my motor to 30+ mph.
 
n2mb said:
Does anyone make a pack with 21700 cells? I just want to buy a pack. I don't have time to build one. I don't really even have time to build an eBike, but I can't buy one with the performance I want... I would have just bought the Sur Ron, if I could get one with a damn VIN and register it as a moped!

Queen Battery does. They can build custom packs according to customer's needs.
 
I think the huge advantage here is if they have a functional balancing circuit! That would allow bulk charging of the series string of LiPos on the bike using a standard ebike charger. I would vastly prefer that then having to take the batteries off the bike every day when commuting...
Perhaps I wasn't clear on balancing. Large packs that don't exceed the 80% dis-charge rule and don't have the "string broken" really don't need balancing, just ck'ed. MY Multistar is so stable, I really can't remember the last time I had to balance any of the cells in it, although I ck at least one brick every charge cycle.
The pack on my frt. motor is quite different. Although it's Multistar too, it's a sm 1P pack that I'm constantly reconfiguring between 12S and 14S. Since I pull those batteries off the bike and "break the string", I balance charge on a cheap RC charger. Since they are disturbed, the cells tend to start to wander. This takes time to double charge, say, three bricks (6S + 4S + 4S + 14S), especially since my charger wants to top charge to 4.20V and by then the cells are scattered and it has to balance, which takes a lot of time. I usually stop them at 4.10V and clean them up a bit w/ a Battery Medic. All and all, I spend way more time fiddling w/ my sm. pack than the , almost "plug and play" big pack that I bulk charge.
It's not cell balancing that is the time user of quality LiPoly, it's getting the Voltages set and matched if one is breaking down the pack to charge and playing around w/ the bricks. The moral of the story is, build a big enough pack that there is no need to charge above 4.10V or dis-charge below 3.70V and don't break it apart and balncing becomes a "thing of the past".
 
n2mb said:
motomech said:
My main pack is 4) Multistar 6S/10,000mAh bricks configured 2S/2P for a 12S(46.5V nom.)/20,000mAh pack. They are currently on sale @ HK for $75 delivered, making my total cost $300.

You are right, though, those 10 ah packs are really cheap! I'd been looking at the 16 Ah and 20 aH ones....

I'm guessing the 10C rating is optimistic, though... Any thoughts on running 3 of them in series and pulling 70A/80A peak from them? I really want 60+ volts to get my motor to 30+ mph.

The Multistar is designed as a trade-off of lighter weight, smaller size and lower volatility rfor a lower dis-charge rate and have their limits.
A member here, icecube57, did some dis-charge testing of the Multistar and published the graphs, but did not report his results in text. I gathered that he felt a 12S/15,000 to 20,000mAh pack could maintain a constant 40 Amp discharge.
On my 12S/5000mAh pack, a 20 Amp controller can pull a 1 to 2 Volts sag at the lower end of dis-charge.
On my 12S/20,000mAh pack, there is no sag right down to the LVC(25 Amp controller).
Any thoughts on running 3 of them in series and pulling 70A/80A peak from them? I really want 60+ volts to get my motor to 30+ mph.
I have read of folks here stating they are getting this kind of performance out of the Multistar, but my gut tells me one would need a pretty big pack to do it.
 
Interesting. I hadn't realized that it would require so little balancing. That could work for me, since my daily commute is only 4 miles. I'd only be draining 20-25% of the pack. I could use the cycle satiator to bulk charge back to 90%, then periodically do a balance charge off the bike.

I'll look for those discharge curves. I'm expecting my continuous draw to be 20 or 30 amps. I'd only hit 70-80 amps while accelerating or climbing a hill (short).

So, I suppose a 18s 10 Ah pack could work for me. I may do that, if I can't figure out how to get my damn triangle pack mounted. I have a 60V 21Ah 16s7p pack, but I can't find a triangle bag that will hold it and fit in the frame... working on that part now. If it doesn't work, I'll get a small bag and throw three lipos in there and go...
 
Back
Top