Zippy Flightmax / Turnigy lipo testing

[GGoodrum]

Fair enough.
Any chance of posting a circuit diagram and component list for those of us who want to play around with different numbers of cells?
Fell free to tell me to nick off if this is infringing on the time / effort you put into testing and making these boards

The circuit couldn't be simpler. It is just 2-1/2 parts per channel. Here's the schematic:




This example includes the active cutoff section, which should be good for well over 100A, but I prefer to use the controller's ebrake input. It is more reliable and works with virtually any ebike controller.

Does this work with the RC ESC or throttle interfaces or servo tester?

Yes, it works with either a servo tester or with Fechter's throttle board, which has a dedicated set of pads for this function. For use with a throttle tester, you simply connect the LVC ground, to the ground on the tester, and connect the LVC "+" lead to the center lead from the potentiometer or the signal lead from a a hall sensor-based throttle.

-- Gary

 

[methods]

WTF ?!?

Crazy..... You can see where things are headed.

-methods

 

[Arlo1]

It would seem we realy need motors that can handle alot more amps!

 

[methods]

I can second that!

Still cant find a fan that will fit inside my V2 X5... 9mm is not much room.

-methods

 

[will_newton]

you just made my day. order placed. thanks!

Okay, I have a pile of 4-pin, 5-pin and 6-pin JST-XH board-mountable connectors coming, so I went ahead and changed the shopping cart item around so you can select the number of cells per pack, from 3s to 6s. Here's the page link.

Edit: I did the same thing for the LVC + Parallel Adapters as well.

-- Gary

 

[GGoodrum]

Thanks, Will.

I've added the 9-3/4"/248mm black PVC shrink tubing and later today, I will be adding the new balancer:

View attachment 12-Cell Charge Balancer-08.jpg

View attachment 12-Cell Charge Balancer-06.jpg
View attachment 12-Cell Charge Balancer-07.jpg

The shunts are set to be fully on at about 4.10V. When the pack is first being charged, in the CC mode, The LEDs are all red. Once a cell gets to about 4.07-4.08V, it starts to transition to green. At about 4.085-4.09V, the LED is orange. Once the voltage hits 4.10V, when the shunt is fully on, the LED is fully green. The transition for fairly well-balanced cells only takes about 1-2 minutes, and the cells all start to transition within 30 seconds to a minute of each other.

View attachment 12-Cell Charge Balancer-11.jpg
View attachment 12-Cell Charge Balancer-12.jpg
View attachment 1
View attachment 12-Cell Charge Balancer-14.jpg


Balancing doesn't take long at all, even for a 15Ah pack, mainly because there's about 600-650mA of balance current available, which is 2-3 times what RC balancers can handle. This makes the box get pretty warm, but the whole case is used as a heatsink. The shunt resistors mount from the bottom of the board, and make thermal contact with the bottom of the case.

Anyway, more about this later. I still need to figure out the cost, etc.

-- Gary

 

[Russell]

...I will be adding the new balancer:


Balancing doesn't take long at all, even for a 15Ah pack, mainly because there's about 600-650mA of balance current available, which is 2-3 times what RC balancers can handle. This makes the box get pretty warm, but the whole case is used as a heatsink. The shunt resistors mount from the bottom of the board, and make thermal contact with the bottom of the case.

Anyway, more about this later. I still need to figure out the cost, etc.

-- Gary

Gary,

So just to be clear this balancer is this designed to be used with TWO (or multiple paralleled) 6S 22.2V LiPo packs? Can it be used with 5S packs? What is the optimal charge voltage to use with the balancer? Can it be left on a pack all of the time? I've never used hobby LiPo packs but you are making it so easy I think I'd like to try them but I'd like to use a couple of 5S 18.5V packs in series to augment my Bosch Fatpacks and charge them with the same charger set to 41.3V. Would this work for me?

-R

 

[mwkeefer]

Gary,

Nice job on the Lipo LVC boards... I will be ordering a few in the next couple of days for a much cleaner interface on my 9FS (finally getting rid of the BM6 units)!

Just to let everyone know... I just received 6 new pieces of 5S from Hobby King - They all tested ok for voltage (pack and cell) but had abnormally high (just in comparison to my previous orders) internal impedance at pack level until I pulled a cycle out of them... now they have normalized to between 0 and 3mohm a cell and all well below 10mohm a pack (more like 4-5mohm per pack).

These beauties are discharged as 15S2P and for now balanced/charged on iCharger 1010B+ @ 10A in 10S3P configuration but soon switching to brick chargers (a few samples finally arrived)...

Currently (pun not intended) they will power a 9FS with a 20" e-bikekit.com 9c (9x7) rear on a stock controller (22a) - in my first discharge test I managed 11miles per 1P in seperated discharge mode... the next run will be in parallel mode.

They will end up in 10S3P config for a 9FS build up around an ms eDrive and a Tower Pro 5330 9T + 3 or 8 spd internal shifting hub.

The build quality seems to have dropped off a bit as they had areas at the caps where I could see the PCBs inside... otherwise I am quite happy with 11mi per pack (from 4.16v initial charge to 3.2v cutout) in 1P and anticipate closer to 25-28mi in 2P config based upon earlier testing. My top spd at the moment on the 9FS with 9c rear is 27mph on flats, down to 21 at cutout.

Hope this helps someone !

-Mike

 

[Hyena]

The circuit couldn't be simpler. It is just 2-1/2 parts per channel. Here's the schematic:

This example includes the active cutoff section, which should be good for well over 100A, but I prefer to use the controller's ebrake input. It is more reliable and works with virtually any ebike controller.

So when the voltage drops to 3v, the output of the optocoupler going to the ebrake wire goes to ground ? If you wanted to, in place of the right hand side of the circuit you could trigger a relay that could actively cut off the main discharge lead couldn't you ? I'm just trying to be lazy with the number of components!

Re: the balancer, can you source a smaller case for a 6S version ? I'm just thinking you might get a bit of interest in your fast high current balancer from the RC world.

Mike weren't you getting much higher speeds from your 15S packs before on that 9C ? Or is this one a different wind ? Or different controller set up ?
Let us know how you get on with those 63v brick chargers!

 

[liveforphysics]

Gary! Awesome work!

Those parts are going to sell like hot-cakes! Thank you for working hard to fill a void in products for LiPo pack powered vehicles.

Any chance of a 20s balancer?

 

[mwkeefer]

Hyena,

Do get much higher speeds on my 26" specialized with a bumped current of 32A - The bike I'm playing with now is a 9FS (2 of them really) - The 9x7 windings with a 20" wheel and the stock infineon 9FET 22A limited controller get me to a flat max (on full charge) of 27-28mph. These motors (9x7 9c) seem to stick around 453 rpm maximum on 62.4v fully charged which would indicate a loaded kv of (453 / 62.5) 7.26 rpm / v. This is only as measured with the Infineon controller and is a stock amperage of 22 with all stock (I assume 100% spd for spd2) speed settings.

When I connect a modified Infineon with higher current limits and optionally advanced speed settings to 120% - I will post a new thread with the effective kv of the 9x7 windings and expected mph/kph speeds from various wheel sizes for reference, also with the modified infineon results (top speeds, accelleration time reduction, current used).

The way to go with Gary's board isn't a relay on the pack mains and in my opinion I wouldn't want my eBrake line toggled either (just in case of regen enabled) but rather I like to toggle the simple 5v throttle return line using a transistor for a relay...

Another method would be the +Ignition wire (if your controller has one, infineon, ecrazyman, etc all have one), this is at pack voltage but the current is some 50ma or so, this allows a very low current high voltage cutout that leaves the packs connected but the "cycle" functions shutdown - useful for logging, etc.

-Mike

 

[GGoodrum]

Gary,

So just to be clear this balancer is this designed to be used with TWO (or multiple paralleled) 6S 22.2V LiPo packs? Can it be used with 5S packs? What is the optimal charge voltage to use with the balancer? Can it be left on a pack all of the time? I've never used hobby LiPo packs but you are making it so easy I think I'd like to try them but I'd like to use a couple of 5S 18.5V packs in series to augment my Bosch Fatpacks and charge them with the same charger set to 41.3V. Would this work for me?

-R

Yes, that's right, it has two independent 6-channel sections. These don't need to be overlapped, like RC balancers, so they can truly be independent. The reason is that the RC units balance to the lowest cell. This one balances to a set voltage point (4.10V...).

Each section could be used with 3s, 4s or 5s packs as well, with a suitable adapter. If the demand is there, I might also offer dedicated versions for these. I will also do a kit version, and for that you can populate each section with however many channels that are required.

The optimum charge voltage would be 4.10V x # of cells, so for a 12s setup, it would be 49.2V. So, if you do two 5s packs, in a 10s configuration, 41.0V would be optimum, but 41.3V would be fine. Just don't charge them in parallel with the Fatpacks.

Although it won't hurt anything to leave the balancer connected, the red portion of the LED will stay on, so it will drain something. One other thing you can do is use the balancer after charging. I've done this when I've quick-charged packs using RC chargers, which are usually set for 4.2V per cell. The balancer works in reverse, starting out with all green LEDs, eventually all turning red. That balanced all the cells to 4.08V.

-- Gary

 

[GGoodrum]

Gary! Awesome work!

Those parts are going to sell like hot-cakes! Thank you for working hard to fill a void in products for LiPo pack powered vehicles.

Any chance of a 20s balancer?

Thanks, Luke.

I can easily do other versions, with more, or less channels, but I want to get a handle on how much heat is generated, with these 6.2 ohm shunt resistors. With 12 channels, in the sealed box (see above...) I was seeing about 150-155F, on the bottom of the case.

-- Gary

 

[GGoodrum]

Hyena,

Do get much higher speeds on my 26" specialized with a bumped current of 32A - The bike I'm playing with now is a 9FS (2 of them really) - The 9x7 windings with a 20" wheel and the stock infineon 9FET 22A limited controller get me to a flat max (on full charge) of 27-28mph. These motors (9x7 9c) seem to stick around 453 rpm maximum on 62.4v fully charged which would indicate a loaded kv of (453 / 62.5) 7.26 rpm / v. This is only as measured with the Infineon controller and is a stock amperage of 22 with all stock (I assume 100% spd for spd2) speed settings.

When I connect a modified Infineon with higher current limits and optionally advanced speed settings to 120% - I will post a new thread with the effective kv of the 9x7 windings and expected mph/kph speeds from various wheel sizes for reference, also with the modified infineon results (top speeds, accelleration time reduction, current used).

I have a 9x7 9C in a 20" folding bike, with one of Methy's 18-FET 100A controllers and an 18s3p Turnigy pack, and it is a beast with 85A/5500W peaks. It tops out at 31 mph on 18s/66V.

The way to go with Gary's board isn't a relay on the pack mains and in my opinion I wouldn't want my eBrake line toggled either (just in case of regen enabled) but rather I like to toggle the simple 5v throttle return line using a transistor for a relay...

The easiest way is to have the LVC opto line pull down the throttle signal. All it takes is the addition of a current limiting resistor:

View attachment LVC Throttle Interface.png

 

[mwkeefer]

Gary,

> I have a 9x7 9C in a 20" folding bike, with one of Methy's 18-FET 100A controllers and an 18s3p Turnigy pack, and it is a
> beast with 85A/5500W peaks. It tops out at 31 mph on 18s/66V

66 * 7.26 = 479 RPM / 366 * 20" = 28.52 mph (3 mph off)

You do get there faster with 5500W peaks... Are you using any of the advanced speed settings offered on the Infineon controller? If not you may squeeze a few more mph off the top of the packs with 110 or 120% speed setting on a push button.

-Mike

 

[GGoodrum]

66 * 7.26 = 479 RPM / 366 * 20" = 28.52 mph (3 mph off)

You do get there faster with 5500W peaks... Are you using any of the advanced speed settings offered on the Infineon controller? If not you may squeeze a few more mph off the top of the packs with 110 or 120% speed setting on a push button.

-Mike

Without much load at top speed, the pack voltage is closer to 67.5-68V, so that is part of the difference. I haven't changed any of the settings in the controller. 30 is faster than I need to go on a folder anyway.

-- Gary

 

[Russell]

Each section could be used with 3s, 4s or 5s packs as well, with a suitable adapter. If the demand is there, I might also offer dedicated versions for these. I will also do a kit version, and for that you can populate each section with however many channels that are required.
-- Gary

Instead of offering dedicated models could you provide two adapters similar to this for your 2x6S version?




-R

 

[snowranger]

Thanks, Will.

I've added the 9-3/4"/248mm black PVC shrink tubing and later today, I will be adding the new balancer:

View attachment 7
View attachment 6
View attachment 5
View attachment 4

The shunts are set to be fully on at about 4.10V. When the pack is first being charged, in the CC mode, The LEDs are all red. Once a cell gets to about 4.07-4.08V, it starts to transition to green. At about 4.085-4.09V, the LED is orange. Once the voltage hits 4.10V, when the shunt is fully on, the LED is fully green. The transition for fairly well-balanced cells only takes about 1-2 minutes, and the cells all start to transition within 30 seconds to a minute of each other.

View attachment 3
View attachment 2
View attachment 1



Balancing doesn't take long at all, even for a 15Ah pack, mainly because there's about 600-650mA of balance current available, which is 2-3 times what RC balancers can handle. This makes the box get pretty warm, but the whole case is used as a heatsink. The shunt resistors mount from the bottom of the board, and make thermal contact with the bottom of the case.

Anyway, more about this later. I still need to figure out the cost, etc.

-- Gary

To also clarify for a newbie, do you need to use a 12s balance charger like this or a bulk cc/cv charger with the balancer?

 

[GGoodrum]

To also clarify for a newbie, do you need to use a 12s balance charger like this or a bulk cc/cv charger with the balancer?

The latter, you use a bulk CC/CV supply/charger.

 

[snowranger]

Thanks. What charger spec do you need then? Is it a non-standard voltage?

 

[GGoodrum]

Thanks. What charger spec do you need then? Is it a non-standard voltage?

For a 12s setup, you need CC/CV-capable supply or charger that can be set to 49.2-49.5V. Most variable supplies will have true constant current limit modes, but most fixed ones do not. I like the Mastech variable supplies. I have a HY5005-2, like this one, which has dual 0-50V, 0-5A outputs. These can be combined in parallel, to do 0-50V, 0-10A, or in series, for 0-100V, 0-5A. They also have another single channel, 20A version, the HY5020E, like this one, which is 0-50V/0-20A. This is not as expensive as you think, when compared to RC-type chargers, because with those, you still need a big 12V AC/DC supply, and none can even do 10A for a 12s setup, much less 20A.

-- Gary

 

[drewjet]

So I ordered myself 6 of the 6s 5000 MAH 20C Turnigy's. Got them in less than a week, WOW! Shipping at $69 kinda hurt, but even so, still a great price. Of the 2 I have charged so far, they are showing an Internal resistance of 1.3 to 1.6

Now the bad news.

1 Came with a slight puff on an end cell, and one came with a cell at 1.0 volts.

What should I do? Charge and see what happens? Send em back?

 

[methods]

wtf?

Why do people keep getting hosed like this?
I must be amazingly lucky.

Go to Hobby city
Open a return request and explain what happened
Dont tell them that you charged anything... Make sure you point out that it was bad right out of the box.
They probably wont honor the puffed cell but they will cover the 1.0V cell.

Wait till they give you instructions

Put the cell in the cheapest mail you can.
Get ready to wait at least a month.

Basically - you need to order replacements. :|

-methods

 

[methods]

P.S. If you run your own cells down to 2.5V or 2.0V by leaving your bike on by mistake you can usually revive the cells. I have many times and in my experience, if they were "trickled" down they usually come back with all their capacity. On the other hand if you hit LVC at full throttle and drive the cells down to 0V under a 10C load they are toast.

Receiving a cell that has been resting at 1.0V is a lost cause.
The IR will be huge you will just get heat when you try to charge it - dont put yourself through the trouble.

-methods

 

[drewjet]

I haven't charged them yet. I checked them as soon as they came out of the box. The puffed one is not that puffy, but was noticable.

I did fill out the form. An autoresponder gave me a return authorization number. Fortunately I really only needed 4 of them, so it's not an end of the world situation.

As a side note, I had a 100 Amp Turnigy ESC go bad after 9 months and they did replace that.