Inteligent BMS with --USB to PC --

[Doctorbass]

Does anyone ordered one of these and tried it yet?

http://www.bmsbattery.com/product_i...d=115&osCsid=edc288f6db4f07aeae8ffc43a595f92a

Specification:

1.Fits for 8~12 Lithium-Ion/LiFePO4 Cells In Series Battery Management System.

2.There is a software and a speciaal USB line to set parameter by connecting BMS to your PC.

3.Can be monitored all the battery pack and cells status by connecting to PC USB port. You can monitor pack voltage,cells volatge,temperrature,charge/discharge current,count of the battery pack lifecycles,parameter and so on.

4.Continuous Discharge Current:20Amps.

5.Peak Discharge Current:40Amps.

6.Overvoltage and Undervoltage can be set by PC computer.

7.Identify how many cells automatically.

8.Has temperature sensor to monitor the battery pack. You can set any temperature you want to protect your battery pack.

Doc

 

[steveo]

that looks good .. and cheap..

but only 12s

doc ... i've been using the mks balancers to moniter my a123 pack and they work great

i set them to start discharging at 3.6v each cell...

i have my psu set at 87v for my 24s pack! and no problem .. i usually charge my 11ah a123 pack in about 2 hrs @ about 7.5amps charge rate!

i love my mks alot more then garys bms .... I've had no problems with them since i've started using them!!

only thing that would be better then this is my kionin pack which i'm in the midest of collecting cells ... at about 160 cells tested!! waiting on more to test for the pack with my dual megapower charger/discharger setup

-steveo

 

[GGoodrum]

They appear to be switching over to this model for everything because they have removed the "bleeding" (shunt-based...) and "capacity" (switched cap...) entries, but still have the categories.

It looks like these are also shunt-based, but with a bit more functionality in the processor and the USB interface. If that's the case, I'm guessing these won't have much in the way of bypass current, probably 50-100mA, like most of these. Having a 20A/40A discharge limit is pretty weak as well, so I'd bypass that, and try and figure out how to tap ionto something that could be used to kill the throttle, or activate the controller brake input. Not sure about the charge current either, as there is no mention of the limit. If it had a decent about of shunt bypass current, it could be used as a standalone balancer for LiPo or LiFePO4 packs. With LiPos, for instance, you could set the over-voltage to 4.25V and the balance point to 4.15V, via the PC interface.

-- Gary

 

[Jeff]

Appears to be from ecity power. And as their banner says: Safer! Laster! Smarter!

http://www.ecitypower.com/

Click to: Products: and then to Battery/BMS

It appears to have some dedicated IC for galvanic isolation. It's too bad they never seem to offer enough channels.

Regards, Jeff

 

[GGoodrum]

There is still nothing about how much "bleeding" it can handle. I suspect if it was anything decent, it would be something they would highlight.

 

[liveforphysics]

With 39 ohm balance resistors, at 4.2v, it could do a max of 100mA. Not very useful for packs getting charged at 10-40amps.

As a side note, the hyperion 12s RC balance charger uses the same rating SMD bleed resistors, and only claims 70mA balance current ability.

On the bright side, it certainly looks simple enough to mount a 5amp TO-92 package transistor (to replace the tiny SMD units) , and mount some big 5w 2-3 Ohm resistors up off the board across where the little 39Ohm SMD units are mounted.

It would be a lot of labor, and end you up with a kinda weird fragile clustered board.

Gary's LiPo balancer with HVC seems like a lot more appealing option IMHO.

 

[amberwolf]

FWIW, that item has had it's specs revised:
"4.Continuous Discharge Current:15Amps. 5.Peak Discharge Current:20Amps." So either it's now a different product at that same link, or maybe someone found it doesn't do what they said and called them on it and they changed it.

I'm kinda sad it's so wimpy--I am looking for a really cheap BMS (DIY would be fine) I can use to build up a LiPo system in 36v 10Ah packs from individual 18650 2Ah cells, and one of these would've been nice.

 

[Doctorbass]

UPDATE:

They seems also to have up to 24s and up to 100A Smart BMS

I found the software in the Download section of their new website:

Here is what it look like:

I'll buy one of their 24s 100A model to test.. I'm waiting for the price.

It seem to have alot of adjustable features thru the software!

Doc

 

[patrickza]

UPDATE:

They seems also to have up to 24s and up to 100A Smart BMS

I found the software in the Download section of their new website:

Here is what it look like:

I'll buy one of their 24s 100A model to test.. I'm waiting for the price.

It seem to have alot of adjustable features thru the software!

Doc

That does look good, I would really love to be able to tweak my maximum charge voltage and cut off voltage on a per cell scale. We could maximize the cell life, and make sure the pack stays well balanced. Hopefully the price is reasonable, and it does what it claims to do. Please keep us informed.

 

[grindz145]

I wonder who's IC they are using for this implementation. I am wondering if these are actually SMBus controlled or some other custom implementation.

 

[auraslip]

Has anyone tried these? I'd like to use them with lipo

 

[BatteryMooch]

I wonder who's IC they are using for this implementation. I am wondering if these are actually SMBus controlled or some other custom implementation.

It's someone's micro, not a dedicated BMS chip IMHO (based on the chip lettering that can be seen on the BMSBattery site).
SMBus is just a standard set of commands and responses using, essentially, I2C comms so basically every chip's implementation is custom. Very easy to set up in any micro so I'm sure it's actually the SMBus command set. I don't know how many of the commands they implement though.

 

[grindz145]

I wonder who's IC they are using for this implementation. I am wondering if these are actually SMBus controlled or some other custom implementation.

It's someone's micro, not a dedicated BMS chip IMHO (based on the chip lettering that can be seen on the BMSBattery site).
SMBus is just a standard set of commands and responses using, essentially, I2C comms so basically every chip's implementation is custom. Very easy to set up in any micro so I'm sure it's actually the SMBus command set. I don't know how many of the commands they implement though.

Yeah, I would be surprised to see any generic chinese setup like this comply with standards, especially a somewhat arcane standard, but it would be really nice to work with if that were the case.

You could imagine the possibility for having universal SAFE charging with that type of implementation though. It could propagate way beyond the casual DIY experimenter.

I have some experience dealing with these guys and it is a pain to say the least. Took about 2.5 months to get ~40 cells. Probably not worth the trouble.

 

[auraslip]

I'm considering building a 12s3p pack out thesecells on sale for $7 each. It'd be 44.4v 6.6ah for ~$90

I want to use one of these "smart" bms,and one of these chargers. $50

(After shipping that is only slightly more than a similar sized SLA pack!

bmsbattery.com will program the BMS and charger to what ever settings you want. What settings do should I use for this hobbycity lipo?

Before anyone says anything about the 10/20 amp limit of the BMS: I will follow hal's advice

I use to buy bms according to current that I use. Now I take the smallest current BMS and connect exit from bms to small power of controller and big wire from controller is connected to battery pack directly via fuse. when bms shuts down it does not cut off main power suply, just controller power.