Bad battery on two year old JB RipCurrent

[daverepair]

I bought a new RipCurrent in March of 2021. Once last summer, and twice this summer, the battery has cut out(or shut off) after about 16 miles of riding. Shutoff occurs when the battery bar shows four or five bars(about 50%). I've only ridden about 400 miles over two years, and only in our Vermont summers(and not in extremely hot temperatures).

JuicedBike Support says the BMS(battery maintence system) chip is defective, and I must send the battery out for repair, which appears to cost(with shipping) upwards of $250.

I am extremely disappointed with this problem, with having to spend significant $ for a fix. And how to know if the repaired battery will be any more durable or reliable? Has anyone else had this problem, and can offer any advice or suggestions?

Dave in Vermont

 

[Explorer-1]

You don't give any information on what it takes to get the battery going again after a cut out.
Repair is expensive, and very hard to diagnose issue without opening battery if it is the battery. It's possible it is something else that is the problem, but we need more information.
if it is the battery and you can't repair it yourself then; Expensive, but i would strongly recommend just buying a new battery when they are on sale.
i have one battery repair described on here, but i don't recommend it for people not experienced in this. I have another battery waiting to be repaired, but it is a smaller one and i have several large ones, so it's been a low priority. Usually the problem is the balance of the cells, vs electronics.

 

[daverepair]

When the battery would cut out, or shut off, I could almost immediately turn it back on(by pressing the button). I could then turn on the controller(battery bar showing 45%), and ride about 100 yards. Shutoff again, and this would repeat 4-5 times, until I got a ride, and brought the bike home in my truck. I would then recharge the battery, to 100%, and the same problem reoccured, after about another 16 mile ride. I have not tried to charge or ride it since.

 

[Explorer-1]

Sounds to me like a bad cell / cell group that is out of balance. You should not charge the battery to full, because it is over charging the other cells to make up the difference of the low group. You could try to discharge the battery by other means and then charge it again. Might bring it back into alignment. If you check the voltage of the battery, you will see when charged it is not exactly correct or what it was before the issue when fully charged, if you paid attention to the voltage, most just look at the bars. Find my battery repair thread and it will explain more.

 

[daverepair]

Thank you, I will look up your repair thread. Would you disagree with JBs tech stating that it is likely a faulty BMS?

And I know see I should remaining battery charge by the voltage reading, not the likely inaccurate bar graphic.

Is there a simple way I can discharge the battery, by other means?

 

[Explorer-1]

Currently, without additional information, yes i disagree with Juiced's current assessment. The BMS is just very primitive, and is not able to always keep the cells balanced. Many reasons for that, to technical for here.

There are many ways for me to discharge a battery, but for someone without components it's not easy and i would not want to risk injury or fire. If you have time you may be able to just put it on the bike and turn the bike on, but don't ride it. For that to work, you have to be able to disable the auto shut off. I can't remember if Juiced options allow for that. That would take a couple of weeks to drain the battery, if it was possible. You may check youtube for other methods that may work for you, but be sure to understand the risk of any method you choose.

 

[daverepair]

Thank you!

 

[teskow]

It could just be the battery is losing contact at the battery plug to the bike. If this happens the plug will arc and cause a burnt plug. I strapped my battery in very tightly so it could not move at all. I sold the RC but had I kept it I would have replaced the battery to bike plug with something much more durable than the stock plug. I was going to extend the wires to a pigtail length with a proper plug that I would plug in before securing the battery in place.

 

[daverepair]

Thanks, but there is no evidence of charring or shorting at the battery plug connector, either in the battery or on the bike.