LBA10 Balancer with M1 Cells?

[BrianG]

I was looking over the documentation for my LBA10 last night and started wondering if it could be used to balance a pack made of M1 cells. The LBA10 works several ways; it cuts off if the pack discharges down to 2.75v (perfect for the M1 cells?), cuts off if any cells goes over 4.3v, and keeps each cell within 0.05v of each other.

So, if I used an M1 specific charger (or do some type of adaptive CC charging so the max voltage doesn't go over 3.6v/cell), I should be able to use this balancer right? Sure, it won't provide the optimum cutoffs, but that's what the charger is supposed to do. But it should keep each cell balanced with respect to each other.

Thoughts?

BTW: I found out the Hyperion 7i does NOT go into a CV mode with lipos; it's more of an "adaptive" CC. When the voltage reaches 4.2v/cell, it simply constantly adjusts the charge current to keep the voltage to that level. I thought that was kinda interesting. Another thing I found out, the powersupply uses boost mode switching. That probably doesn't mean much to most people, but this charger uses the battery voltage to determine the power supply voltage. The circuitry simply boosts the 12v input to a point a little higher than that. Pretty simple yet effective. :)

[MetalMan]

Some balancers will only balance packs where the voltage is 3.3v or above. I don't know if this balancer operates that way, but if it doesn't, then it's fine to use on the A123 cells.

[BrianG]

Hmmm, it doesn't really say. It just states the cutoff on discharge, cutoff on charge, and the fact it keeps the cells within 0.05v from each other. I really think it does, because when I plug in my depleted (~3v/cell) emoli pack, it starts to balance them right away.

[MetalMan]

Then I guess the answer is yes, it will work :).

[BrianG]

Cool. :dft003:

Now all I need is a charger capable of a 3.6v/cell limit (or do the adaptable CC thing) and the batteries. I may try 6s M1's in my Revo if I can figure out a workable layout.

[MetalMan]

There are a number of chargers out that already have the capability to charge A123 cells, include the TME Xtrema, TP-1010C (soon), Schulze chargers (upgraded firmware), Orbit Microlader (I believe), CellPro 4s, and the Astroflight 109 should be getting an upgrade chip soon. Otherwise, the LipoDapter will allow any charger to work :).

[neweuser]

Originally Posted by BrianG

BTW: I found out the Hyperion 7i does NOT go into a CV mode with lipos; it's more of an "adaptive" CC. When the voltage reaches 4.2v/cell, it simply constantly adjusts the charge current to keep the voltage to that level. I thought that was kinda interesting. Another thing I found out, the powersupply uses boost mode switching. That probably doesn't mean much to most people, but this charger uses the battery voltage to determine the power supply voltage. The circuitry simply boosts the 12v input to a point a little higher than that. Pretty simple yet effective. :)

Not to Hijac a thread here, but I'm curious to what you just said about the Hyperion. Mine will have no problem doing my 4s in series, and as you know all to well Brian, I cannot get the 5s to charge (unless the packs are half charged already), so would this mean that the input voltage is too low to charge my 5s? If so, can I get my powersupply to push enough volts to charge my 5s?:032:

[BrianG]

Originally Posted by neweuser

Not to Hijac a thread here, but I'm curious to what you just said about the Hyperion. Mine will have no problem doing my 4s in series, and as you know all to well Brian, I cannot get the 5s to charge (unless the packs are half charged already), so would this mean that the input voltage is too low to charge my 5s? If so, can I get my powersupply to push enough volts to charge my 5s?:032:

That does sound like a P/S issue. What error message do you get?

If you are getting no charger errors, depending on what amperage you are trying to charge at, you might be hitting the 120w limit of the charger. With a 5s pack, you can only charge at 5.71A (assuming cells are at 4.2v/cell). With 4s, you can charge at 7.14A before you hit the 120w limit. Actually the Hyperion can only go up to 7A, so that will really be the limiting factor at 4s.

[neweuser]

Originally Posted by BrianG

That does sound like a P/S issue. What error message do you get?

If you are getting no charger errors, depending on what amperage you are trying to charge at, you might be hitting the 120w limit of the charger. With a 5s pack, you can only charge at 5.71A (assuming cells are at 4.2v/cell). With 4s, you can charge at 7.14A before you hit the 120w limit. Actually the Hyperion can only go up to 7A, so that will really be the limiting factor at 4s.

If I remember right, output voltage too low is the error message. It has been awhile though. Or it said input voltage is too low. It would say it with the 5s even charging at 2 amps. The 4s I can charge at 5 or 6 no problems at all. I was just curious, if I could bump up what the PS is putting to the charger if this would help charge the 5s if ever needed. My 989 can do it no problems.

[BrianG]

I'd imagine you got an "input voltage too low" message if it was a power supply issue. As the current goes up, the voltage output of the PS will start to fall depending on the build quaility. However, if it does that at a low 2A, that doesn't make sense.

I've also seen "output voltage too low" and haven't really figured out why it does that. From what I could tell, since the circuitry does an adaptive CC charge for lipos, the sensing circuitry is a bit too sensitive and trips the alarm.

I did notice about 14mV of 53kHz AC ripple (from the charger's power supply) on the output connectors. I thought maybe the sense circuit was seeing this ripple causing the alarm to trip, so I tried using an inductor and capacitor network to kill the ripple, but it still had the "output voltage too high" error. I just have to manually adjust the current for now until I figure out why it does this. Eventually, I plan on getting a better charger that will do higher cell counts at higher currents, but it is a PITA for now.

[neweuser]

Originally Posted by BrianG

I'd imagine you got an "input voltage too low" message if it was a power supply issue. As the current goes up, the voltage output of the PS will start to fall depending on the build quaility. However, if it does that at a low 2A, that doesn't make sense.

I've also seen "output voltage too low" and haven't really figured out why it does that. From what I could tell, since the circuitry does an adaptive CC charge for lipos, the sensing circuitry is a bit too sensitive and trips the alarm.

I did notice about 14mV of 53kHz AC ripple (from the charger's power supply) on the output connectors. I thought maybe the sense circuit was seeing this ripple causing the alarm to trip, so I tried using an inductor and capacitor network to kill the ripple, but it still had the "output voltage too high" error. I just have to manually adjust the current for now until I figure out why it does this. Eventually, I plan on getting a better charger that will do higher cell counts at higher currents, but it is a PITA for now.

I see. How would I get my PS to send more juice the charger if this is the case. Anyway, I love the 989 Brian. I'm not a big fan of MRC, but this thing rocks! It charges anything I throw at it. And the price dropped to 135.00 somewhere I saw, can't remember where. sjcrss knows though, you could shoot him a PM if you were interested.

[Serum]

Brian; i am using a Graupner type of thing of these chargers, i can confirm that they are very precise in balancing.

With or without the charging process active, it simple balances them.

If your charging voltage stays at the fixed 3.6V i see no problems for using it for balancing. A nice safety feature is that the 4.3V cutoff really cuts the balancer loose from it's charging signal.

[BrianG]

Originally Posted by Serum

Brian; i am using a Graupner type of thing of these chargers, i can confirm that they are very precise in balancing.

With or without the charging process active, it simple balances them.

If your charging voltage stays at the fixed 3.6V i see no problems for using it for balancing. A nice safety feature is that the 4.3V cutoff really cuts the balancer loose from it's charging signal.

That's good to know. I saw that there were several chargers capable of charging M1 cells, but didn't see anything meant explicity for balancing them. Once I realized how the balancer actually works, it made sense that it would work for these cells even though it wasn't explicitly designed for them.

Like I said, the charger will provide the floor and ceiling cutoffs for the pack. The balancer will simply keep each cell equalized with respect to each other.

[MetalMan]

Originally Posted by BrianG

That's good to know. I saw that there were several chargers capable of charging M1 cells, but didn't see anything meant explicity for balancing them. Once I realized how the balancer actually works, it made sense that it would work for these cells even though it wasn't explicitly designed for them.

Like I said, the charger will provide the floor and ceiling cutoffs for the pack. The balancer will simply keep each cell equalized with respect to each other.

I just read that Astroflight is coming out with an A123 Blinky balancer and a 109 charger that will support A123 cells (not sure on the specifics, though).

[neweuser]

Originally Posted by MetalMan

I just read that Astroflight is coming out with an A123 Blinky balancer and a 109 charger that will support A123 cells (not sure on the specifics, though).

that will make brian happy!