I removed all the head shrink on the Whale Shark battery and checked the BMS card and found that the voltage wasn't correct so I purchased a new BMS card, installed and still had a problem. After a closer look one of the nickel strips does not connect to the -end of the battery it comes right up to the edge and stops. I think it might have had a little contact with the - end of the battery in the beginning and that might be why the battery worked for a few hundred miles. The whole group of 14 cells read 1.75volts. The balance wire for the group is connected to the cell that doesn't have a strip ( this is how I really found the problem when I was connecting the new BMS card)The battery doesn't have a warranty and I have tried to ship it back but no one will ship a battery with that many watt hours. Any suggestions on what I can do? Like trying to solder a wire to connect to the nickel strips and see if they will charge up. Do I need to use a nickel strip? This my first time working on a battery of this type and have way too much money in it to throw it away. Please any suggestions will really help.
Update on Battery Shut Off ,and Help
- Thread starter TLC
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Nickel is your best bet for connecting that battery back up. You can see that it is spot welded for all the other connections, not having a spot welder you could probably solder a jumper across to salvage the pack.
Just don't solder in the center of the negative portion of the cell. Those cells don't like heat in the center where the internal connections are.
Losing one cell out of your probably group of (4) per series connection will not kill your battery. You just lose 25% capacity, think weakest link. Your sensing wire looks to be connected to the main pack and it picks up its voltage state from the other 3 batteries, the 4th battery is just a bonus.
That being said what was the original issue with the pack? Voltage not correct between the charge and load plug? Did you try to reset BMS? Just unplug the white sensor harness from the BMS and plug back in and check your volts at the charge and load plug. If they read the same your BMS is ok and it just tripped is all, if the voltage is still different then it's the BMS.
"The whole group of 14 cells read 1.75v"????? Or just the one that became separated?
If the pack has 14 groups in series it's a 52v battery. If you read #1 group Neg to #14 group Pos what is the voltage?
Just don't solder in the center of the negative portion of the cell. Those cells don't like heat in the center where the internal connections are.
Losing one cell out of your probably group of (4) per series connection will not kill your battery. You just lose 25% capacity, think weakest link. Your sensing wire looks to be connected to the main pack and it picks up its voltage state from the other 3 batteries, the 4th battery is just a bonus.
That being said what was the original issue with the pack? Voltage not correct between the charge and load plug? Did you try to reset BMS? Just unplug the white sensor harness from the BMS and plug back in and check your volts at the charge and load plug. If they read the same your BMS is ok and it just tripped is all, if the voltage is still different then it's the BMS.
"The whole group of 14 cells read 1.75v"????? Or just the one that became separated?
If the pack has 14 groups in series it's a 52v battery. If you read #1 group Neg to #14 group Pos what is the voltage?
harryS
Well-Known Member
"The whole group of 14 cells read 1.75V."
I also question this. You must be measuring at the output of the battery, and the BMS has turned off the output. Find the positive and negative ends of the cells. Measure there.
Then the next step to to start from one end, and write down the voltages of all 14 cell groups. The data gives a rough idea of the battery health. If any are lower then 3 volts, the BMS will shut the battery off. This will depend on what the BMS uses as its low voltage alarm. It's usually around 3 volts, sometimes a tiny bit lower. You really need to find out why the new BMS is not working.
The two solder joints we see in the pictures are made by you when you changed the BMS?
I also question this. You must be measuring at the output of the battery, and the BMS has turned off the output. Find the positive and negative ends of the cells. Measure there.
Then the next step to to start from one end, and write down the voltages of all 14 cell groups. The data gives a rough idea of the battery health. If any are lower then 3 volts, the BMS will shut the battery off. This will depend on what the BMS uses as its low voltage alarm. It's usually around 3 volts, sometimes a tiny bit lower. You really need to find out why the new BMS is not working.
The two solder joints we see in the pictures are made by you when you changed the BMS?
I think those solder joints are original. As long as he used the same BMS or one that accepts the same sensor harness plug there's no need to swap out the sensor wires. 1.75v has gotta be just one cell value.
Start at group #1 Neg terminal and measure between that point and group #1 Pos terminal and write down that #. Then go to Groups 2,3,4,5,6,7,8,9,10,11,12,13,14 Pos terminal and see what the values are. If the battery is charged up you should have around 4-4.2v per group. If its less then you have a battery issue.
Start at group #1 Neg terminal and measure between that point and group #1 Pos terminal and write down that #. Then go to Groups 2,3,4,5,6,7,8,9,10,11,12,13,14 Pos terminal and see what the values are. If the battery is charged up you should have around 4-4.2v per group. If its less then you have a battery issue.
I disassembled the battery and one cell read .86volts and six other read 1.1volts. All other 84 cell read 4.2 volts. Guess one cell went bad and ruined the other six in parallel . Going to use the good cells to build a new battery and just discard the seven bad cells. The battery was built using Samsung INR18650-29ea it lasted four hundred miles total I could tell something was wrong with the battery much earlier. Have ordered a Vruzend kit to build a new battery with the remaining 84 good cells. I think I will build a 6x13 battery. Just my luck my first e-bike and I purchased what I thought was the best battery I could get $699 Whale Shark, just to have a couple cells go bad. But just look at what all I have learned. LOL Thanks for all the help. I know at times I don't make a lot of since I'm just learning and get a little upset at times. Once again Thanks
harryS
Well-Known Member
I believe you got screwed by your vendor. They sold you a defective, overpriced battery, and voided the warranty on the whole system because you tuned up the BBS02 firmware? I certainly will point anyone who asks about Ebike Essentials to your thread.
So you already cut all 84 cells out of the 13x7 matrix? If you have not, I think it will be easier to purchase 7 more 18650 cells and replace the bad cell group. I think the Vruzend concept works with 10x2m 10x3, 13x2, 13x3, but can be problematic with larger arrays just based on users coming to forums like this with complaints. Hard to maintain contact on all those cells with the weight/flex of a big battery.
The good thing is you realize those cells at 1.11V and .86 volt are dead. They cannot be safely recharged once thwy've gone that low.
So you already cut all 84 cells out of the 13x7 matrix? If you have not, I think it will be easier to purchase 7 more 18650 cells and replace the bad cell group. I think the Vruzend concept works with 10x2m 10x3, 13x2, 13x3, but can be problematic with larger arrays just based on users coming to forums like this with complaints. Hard to maintain contact on all those cells with the weight/flex of a big battery.
The good thing is you realize those cells at 1.11V and .86 volt are dead. They cannot be safely recharged once thwy've gone that low.
Good luck breaking out all the other good cells in that pack. Looks like a single pair spot weld per battery. I used the Vruzend kits for awhile but always had connections coming loose. Assembled make for a larger size pack with the lego's. Easier to build for sure. Good luck.
Yes I got screwed but I will just think of it as a learning lesson. I have separated all cell, I couldn't see anyway I could replace the bad cell unless I removed all cells then replace the bad one and then spot welded all 91 cells. I guess I might have to buy a spot welder if the Vruzend kit doesn't work. I purchased the Vruzend kit with the bolts to secure the ends hoping they won't loose contact. As I have said earlier I was going to ship the battery back anyway, took it to local pack and ship they wouldn't ship the battery and sent me to the UPS store UPS store wouldn't ship because on total watthours they said it was too large. The told me I would have to ship it by freight line and that would cost around $500. So how does one ship a large battery anyway? I planning on building the Vruzend battery on a peace of aluminum, with the aluminum being inside the shrink wrap and used to mount the battery to the bike. What the hell if it doesn't work I will have another learning experience. I don't really mind all the troubles because the Bacchetta is a blast to ride with the Bafang kit. Rode yesterday too test the new Amazon battery 14.4 ah, rode in level 2 (20%) 62 miles with 1500 feet of climbing averaging 19.4 MPH with the last couple of miles using throttle only just to drain the battery. Battery was at 10% when I stopped. I was working hard the whole time but I ride that way anyway so why not have the added speed. I check the bike after the ride and one thing I noticed I will be need brake pads soon, small price to pay for all the speed. Told my wife this is as close to a motorcycle as you can get on a bike. Thanks
Gionnirocket
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Excellent attitude
One thing that you can try with your repair is to go a little above and beyond and use some adhisive silicone to help hold the cells in place in conjunction with the Vruzend. Some silicone on the nuts and outer bolt thread will also keep them from vibrating loose. Downside is that it can get messy if you're not strategic and patient in the application. Perhaps shrink wrap the beast afterwards as well.
Yeah... Forget about shipping a battery... not really end user doable as it will cost more than the battery is worth.
I might use a little Loctite on the nuts and will look at using hot glue or some type of silicone to secure the batteries to each other. I'm hoping if I install a piece of aluminum along the bottom of the battery and attach it with hot glue or silicone to the bottom row of cells and then tape and heat shrink it all together it might be ridge enough. I plan on having a couple bolts threaded into the aluminum plate which will stick out thru the heat sink and bolt into the battery holder. The way I look at it whats the worst that could happen if battery looses connection I will just have to ride home on my own power something the first battery taught me was possible. Thanks
Gionnirocket
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The reason I didn't recommend locktite as it might interfere with the electrical integrity of the connections. I think I would get it all together and then strategically get some silicone between the cells and over the nuts... JMO...no experience doing so.
Hot glue is good for holding stationary things together, but I don't feel it's as flexible as silicone and it can break free. Perhaps a bit of both? Probably over_overkill. I think a layer of heat shrink just on the cells (above the bottom Vruzend and below the top Vruzend) and then another over the whole thing would make it bulletproof.
Keep us (me :- ) updated as I may attempt a similar project
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