Bantam PB-6 Balancer

[momo]

http://www.bantamtek.com/Manual/PB-6%20English.pdf

http://www.bantamtek.com/
http://www.scalerchelis.com/phpBB2/viewtopic.php?p=73424&sid=ea1dc4c052ba544ff1a6c75d12df8123

Another balancer idea. I want to install this balancer together with the battery pack wired all the time 24/7. Do you guys think by doing that the cells will be drained? This balancer must be disconnected and reconnected in order to turn it on after it shuts down. Once the balancer is plugged into the battery the balancer turns on and begins balancing. The problem is that after it is finished, the balancer shuts down. If i were to add a switch to the power pin of
the amtel would that work (or a reset)

This balancer might not be all that great anyway. During a charging cycle if any cell voltage passes 4.23v the buzzer
sounds and will continue to charge. Not good if your not nearby to stop the charging manually. The nice thing is
that you can monitor each cell voltage on the charger display or your computer with the usb port. Keeping a charge history
log on your computer.
View attachment P1010346.JPG

 

[fechter]

At 200uA, I wouldn't worry about the drain. Depending on your battery size, it might take a year to drain. As long as you cycle the battery more than once a month or so, I don't think it would be an issue. If you store the battery for a long time, disconnect the balancer.

It seems like there should be an interface between the balancer and the charger to cut the power once the cells reach max charge voltage. The 'temperature probe port' might have the right signal in there, but it looks like a serial data port.

It might be possible to tie into the 'buzzer' and use that to trigger the charger off.

The Atmel should have a reset pin somewhere, or if you interrupt the power to the chip, that will reset it too. You might be able to just put a switch in series with one of the battery wires, probably the + side.

Can you read the numbers off the chips?
Sometimes they gind them off, but do a lousy job so you can still read part of them.
I'm interested in how they are doing the voltage measurement, triggering the load resistors, and communicating to the next module.

Perhaps a super close-up pic of the board would be nice if your camera can do that.

 

[safe]

Oh that's hilarious... $50 bucks and you get a full blown balancer for 6 cells and so for $100 you could do 12 since they can be linked together. That's great. And with a USB port you can even read what's going on.

So the bar is set so that you need to be able to build a balancer (if you wanted to compete with this) so that the component list is so short and the features so favorable that you can beat $100 bucks for 12 cells.

That's tough to do... :lol:

"We guarantee the final voltages are nomalized with an accuracy less than 0.01V."

http://www.rcaccessory.com/index.asp?PageAction=VIEWPROD&ProdID=191

$49.95

However, I do have to caution that the chargers for these don't put out much power... something like 50 watts... so you really need to use this with something like the smaller cells more like what you have with RC equipment. For something massive like a 40Ah Thundersky cell I doubt that it could take 1000 watts of charging power.

 

[momo]

Actually i have tried to disconnect the + side power wire with no luck. The other cells
will feed the balancer, You have to disconnect and reconnect in order to re-activate. Notice the two
zener diodes next to the cnrd2951 wired to pin 8 through a resistor 100ohm and a capacitor. The one end
of each zener goes directly to two cells only (2 and 3). that might be how power is feeding everything?

You can only use either the temp sensor which is actually an LM350dz to-92 case
or the PB6 balancer one at a time not both. They plug into the same port on the
charger. When using the temp sensor the charger will shut down once the temp reaches
your selected range.

I did think of Tying the buzzer to trigger the charger off but don't know
how.

Here are the IC parts:
1-LM358
1-LM324DG
1-ATMEL ATMEGA8L 8AU 0717I 32pin
1-CNRD2951 - do not know what this part is, could not find it. Looks like
it is wired to the center cells through zener diodes. That might be where the power
comes from to feed the ATMEL and everything else.

I have taken high resolution photos 2.83mb which look really good, but need to down size them

 

[momo]

http://i124.photobucket.com/albums/p30/bellamari184_photos/P3050219.jpg

http://i124.photobucket.com/albums/p30/bellamari184_photos/P3050217.jpg

http://i124.photobucket.com/albums/p30/bellamari184_photos/P3050216.jpg

http://i124.photobucket.com/albums/p30/bellamari184_photos/P3050215.jpg

http://i124.photobucket.com/albums/p30/bellamari184_photos/P3050214.jpg

 

[momo]

here is the atmel
http://pdf1.alldatasheet.com/datasheet-pdf/view/80260/ATMEL/ATMEGA8L.html
I still cannot find the cnrd2951.

 

[momo]

Looks like the cnrd2951 is made by national semiconductor. LP2951 keeps comming up after a
search, which is a voltage regulator.

http://www.national.com/mpf/LP/LP2951.html

 

[fechter]

Thanks for the pics. I think you got it on your hand drawn schematic. Switch the input to the voltage regulator to reset the Atmel.

I see a pair of optocouplers. I wonder what they're doing?

I'm sure there's some way to make an automatic cutoff for the charger, but it might be a bit crude.

 

[momo]

Fechter, I traced the optocouplers for you. The one on the left is wired directly to the chrger link - and + terminals.
The other is wired to the 12 series expansion link. They are using the optocouplers to communicate to the charger
and the next PB6 balancer. The blank solder holes on the board must be how they program the ATMEL. The board
is very high quality with atleast tripple layers.

 

[dirty_d]

you can reset the amtel avr by pulling the RESET pin(1) low.

 

[momo]

Thanks Dirty_D,
My drawing did the job. Killing the power on everything is better anyway.

 

[fechter]

Seems like the signal to kill the charger should be on the opto.

 

[Doctorbass]

Hey guys, The LCB-12s do a great job too!

12s ONE balancer!

-compatible with many charger or it can be used stand alone.

-LiFe and LiPo

-10A

-balancing current 70mA (approx)

69.99$

Doc

 

[fechter]

Doc, that looks cool.
Anybody got a picture of the insides of that one?
70ma would be a bit wimpy for larger packs, but would work if you're not in a hurry.

 

[Jozzer]

I found the infineon useless for large packs, it never once got "there", even when I tried 5 mins after balancing the pack with another balancer. This was a 50AH pack..
It's great for 1p packs of A123's though
The voltage readout is very usefull too, displays graphs or figures to let you see where each cell is at. I sometimes use it for monitoring, whilst balancing with a faster homebuilt jobbie.

 

[Doctorbass]

The best Balancer/Display meter is The MKS propo 6s

That's one of the fastest balancer.. it bleed 450mA at 4.2V/cell

The Battery Meter/Balancer/Discharger is designed for Li-Polymer and Li-Fe battery, it can measure battery voltage precisely and execute balance work for series batteries, or for battery discharge in order to for long time storage to avoid battery damaged. It can be used as a portable battery meter as it is lightweight, self-contained and with a large display. You can also bring the Balancer to the flying field for battery checking purpose.

The product balance function can allow battery execute balance function before/after charge and using(discharge), also can match-up market string voltage charger to execute devide voltage balancing function while charging.

The product is used big size screen, it can show 6 cell batteries condition. It only uses 3 key to control all function, user can judge batteries condition soon, and can operate all function single-handed.

Thermal-backplane ventilation design, to prevent overheating.

Backplane heat, dust invasion can be avoided, better heat dissipation effect.

Don't worry about the temperature when the unit is in operation.

Supports 2 ~ 6 Cell Balancing tabs

Allows Li-Polymer/Li-Fe 2 ~ 6 Cell balancing and discharge

Included JST connectors and Another receiver power connectors.
--------------------------------------------------------------------------------
Specifications：
1. Product specification: ( CE certificate & ROHS compliant ) LxWxH : 93.5 X 60 X 17 mm
2. Measureable battery type and amount: Li-Polymer/Li-Fe 2 ~ 6
3. Cell(standard voltage 7.4 V ~ 22.2 V using divided voltage joint).
4. Receiver battery 1.2 V ~ 8.5V DC (Not limit battery type, but need external power source 7.4~11.1V, use JST joint)
5. Balance voltage setting range(lower limit):2.0V ~ 3.9V(pre-setting value 3.2V)
6. Discharge voltage setting range (lower limit):3.0V~ 4.2V(pre-setting value 3.9V)
7. Net weight is 70g without package.
8. Max. bleeding current : 450 mA ( at 4.2V / cell )


It only cost 50$.. so for displaying all cell voltage at the same time and the total pack.. that's a great deal!!


[youtube]VJiEivX__Yw[/youtube]

Doc

 

[shinyballs]

The best Balancer/Display meter is The MKS propo 6s

That's one of the fastest balancer.. it bleed 450mA at 4.2V/cell

hermal-backplane ventilation design, to prevent overheating.

Backplane heat, dust invasion can be avoided, better heat dissipation effect.

Don't worry about the temperature when the unit is in operation.

Supports 2 ~ 6 Cell Balancing tabs

Allows Li-Polymer/Li-Fe 2 ~ 6 Cell balancing and discharge

Nice balancer... not meaning to hijack this thread. Can you use 2 of this mks balancer and charge a LiFe pack using an adjustable 400 watt or higher power supply at the same time?

documentation -