Issue with 5s LIPO brick.

[Paderolis]

Hello everyone! I am having an issue with one of my 5s LIPO bricks. When I use the balance lead, it is showing that the 3rd cell only has around 1.3V and the charger does it's job and cancels the charge. However if I only use the positive and negative leads, without the balance plug, it shows the brick to have 21.00V and after less than a minute it says it is full. The weird thing is when the balance plug is used, the other 4 cells don't show a voltage over 4.20V each. I've checked the balance wires on the brick and all seem to be intact, I also moved the brick to a different charging port on my 4 battery charger but I get the same result.

 

[amberwolf]

What does an independent volt meter show for each cell and the whole pack?

Both when disconnected from the charger, and during charge?

The charger could have a problem with the balance port on that cell. Are the ports for each battery actually independent chargers? Or are they just a paralleling board?

The pack could have a problem with the sense wire to that cell, or the cell itself could have high internal resistance. Either one could cause it to show a higher voltage on that cell while current is flowing thru the pack, and a lower voltage when it is not flowing.

 

[Paderolis]

Here is the charger I am using: https://www.googleadservices.com/pagead/aclk?sa=L&ai=DChcSEwiylLTouYTUAhWWVBgKHePcCwIYABANGgJsZQ&ohost=www.google.com&cid=CAASE-RoltKXmL4NckA56d81wvILcjs&sig=AOD64_169uoxRk-O0fMh6DgY0v9u8w89NQ&ctype=5&rct=j&q=&ved=0ahUKEwjcmbHouYTUAhUFIpoKHb8ZBrUQvhcIMg&adurl=

I believe it 4 individual chargers in one.
Okay, I'm only getting 17.72V with an independent voltmeter, so it looks like the cell is indeed bad. I use 3 5s bricks to power my 48V 1000W RHM, these were only bought a few months ago this year. And all at the same time. Looks like I'll be replacing a brick already! Thanks, amberwolf, for your response.

 

[MadRhino]

You can bypass the bad cell and run 14s. Keeping it in the series is dangerous for fire.

 

[motomech]

Here is the charger I am using: https://www.googleadservices.com/pagead/aclk?sa=L&ai=DChcSEwiylLTouYTUAhWWVBgKHePcCwIYABANGgJsZQ&ohost=www.google.com&cid=CAASE-RoltKXmL4NckA56d81wvILcjs&sig=AOD64_169uoxRk-O0fMh6DgY0v9u8w89NQ&ctype=5&rct=j&q=&ved=0ahUKEwjcmbHouYTUAhUFIpoKHb8ZBrUQvhcIMg&adurl=

I believe it 4 individual chargers in one.
Okay, I'm only getting 17.72V with an independent voltmeter, so it looks like the cell is indeed bad. I use 3 5s bricks to power my 48V 1000W RHM, these were only bought a few months ago this year. And all at the same time. Looks like I'll be replacing a brick already! Thanks, amberwolf, for your response.

You are quick to blame the LiPoly, but we know from this thread;

https://endless-sphere.com/forums/viewtopic.php?f=3&t=68613&p=1035129#p1035129

That you didn't understand how and if, the LVC in your display/controller works.
To run LiPoly on an ebike, one needs to be absolutely sure the what the value of the LVC is, that it matches the pack and that is working.
Given that your pack is 3S/1P, it seems like you have put it together w/ an eye towards max. speed w/out much thought about capacity and how a limited capacity(you don't tell us the capacity of your bricks)makes it difficult to stay within the "Never discharge more than 80%" rule. Any chance you over-discharged the pack?
Running Lipoly w/ the "auto-ranging LVC displays is tricky. I know because I tried them out years ago and the display didn't like the odd Voltage of LiPoly and I didn't trust it and went w/ a controller w/ a hard and fast LVC that matched my pack.
At this point, what you need to do is;
1)carefully peal back the plastic that covers the wiring on the top of the brick to access the solder points.
2)Then you need to eliminate the bad cell, not physically, leave it there, but electrically. You do that by desoldering a connection point of the bad cell and "jumping" it with a lead. This requires some skill and probably a 30 Watt soldering iron.

Providing you are able to do this, you then need to establish you have a LVC that is correct for 14S and that it works.

Better yet, start over w/ a pack that has a more reasonable capacity for an obviously power hungry system that has some reserve(at least 10Ah). Leave it at 14S at the most so you can bulk charge w/ something like the Satiator or a Mean Well HGL-320-54A. A much better way than using a toy charger and "breaking" your pack every time to charge.

 

[Paderolis]

You can bypass the bad cell and run 14s. Keeping it in the series is dangerous for fire.

I am not using the brick at all right now and actually have it in a BBQ pit. The bad cell is in the middle, I've watched a few videos on YT, but am still not clear on how to eliminate it.

 

[MadRhino]

It has 2 tabs, one is a - connected to the + of the previous cell, the other is a + connected to the - of the next cell. Bypassing a middle cell is connecting neighbour cells to series together and cutting one of the tabs of the bad cell. You leave it there, it is not dangerous anymore.

 

[Paderolis]

Here is the charger I am using: https://www.googleadservices.com/pagead/aclk?sa=L&ai=DChcSEwiylLTouYTUAhWWVBgKHePcCwIYABANGgJsZQ&ohost=www.google.com&cid=CAASE-RoltKXmL4NckA56d81wvILcjs&sig=AOD64_169uoxRk-O0fMh6DgY0v9u8w89NQ&ctype=5&rct=j&q=&ved=0ahUKEwjcmbHouYTUAhUFIpoKHb8ZBrUQvhcIMg&adurl=

I believe it 4 individual chargers in one.
Okay, I'm only getting 17.72V with an independent voltmeter, so it looks like the cell is indeed bad. I use 3 5s bricks to power my 48V 1000W RHM, these were only bought a few months ago this year. And all at the same time. Looks like I'll be replacing a brick already! Thanks, amberwolf, for your response.

You are quick to blame the LiPoly, but we know from this thread;

https://endless-sphere.com/forums/viewtopic.php?f=3&t=68613&p=1035129#p1035129

That you didn't understand how and if, the LVC in your display/controller works.
To run LiPoly on an ebike, one needs to be absolutely sure the what the value of the LVC is, that it matches the pack and that is working.
Given that your pack is 3S/1P, it seems like you have put it together w/ an eye towards max. speed w/out much thought about capacity and how a limited capacity(you don't tell us the capacity of your bricks)makes it difficult to stay within the "Never discharge more than 80%" rule. Any chance you over-discharged the pack?
Running Lipoly w/ the "auto-ranging LVC displays is tricky. I know because I tried them out years ago and the display didn't like the odd Voltage of LiPoly and I didn't trust it and went w/ a controller w/ a hard and fast LVC that matched my pack.
At this point, what you need to do is;
1)carefully peal back the plastic that covers the wiring on the top of the brick to access the solder points.
2)Then you need to eliminate the bad cell, not physically, leave it there, but electrically. You do that by desoldering a connection point of the bad cell and "jumping" it with a lead. This requires some skill and probably a 30 Watt soldering iron.

Providing you are able to do this, you then need to establish you have a LVC that is correct for 14S and that it works.

Better yet, start over w/ a pack that has a more reasonable capacity for an obviously power hungry system that has some reserve(at least 10Ah). Leave it at 14S at the most so you can bulk charge w/ something like the Satiator or a Mean Well HGL-320-54A. A much better way than using a toy charger and "breaking" your pack every time to charge.

The comment I posted in the link you provided was only because someone had stated you need AT LEAST 44.4V for a 48V system to work. I was just saying that I have powered my 48V 1000W system with only 2 18.5V bricks (42V FOC) and it still worked. This was only done once, however.

I've been using the same setup for over 2 years. The first batteries were 18.5V 4,500 mah 30C. The new ones are 18.5V 5,000 mah 30C. They are even the same brand. As far as having my bike setup for max speed; I use pedal assist only and rarely even go above level 3 of 5! My throttle is installed but unplugged, something I've mentioned a few times in other threads. I keep the multi charger at work, and can usually charge the pack at work, ride home (about 5 miles) and then ride to work again on the same charge with plenty of juice left in each cell. It helps that the commute to work is flat and downhill so I only use level 1. For the short time as I've had them' the cell should not have failed so soon, IMO. It is the only one that did, so yes, I'm blaming the cell! As for using a "toy" charger; this one has worked great and still does, I'm quite happy with it!