Li battery cutting out

[NZgeek]

Thanks,

Yeah, 33A sounds a lot to me anyway! I've just updated my battery connectors from 30A rated ones, to 75A rated ones

It is the Golden Motor Battery setup (that comes in the big alloy case, but I've taken it out now) - it has the rectangular cells. It's "supposed" to be capable of 36A continous (3C), and 60A peak (5C). I didn't think I'd ever be near those numbers though!

So I guess you're thinking voltage sag too? From too much current draw? It's supposed to be a 500W motor.

I guess I could do a shunt mod, or use a cycle analyst to limit draw.

 

[mountainsport]

I think you'll have to wait for the meter to see what's happening unless you can figure out a way to connect a multi-meter while you're riding.

What's the voltage hot from the charger and after it's cut out? We did have one of those chargers that cut out before the battery was half charged, and it finally stopped charging even though it was still giving 43v and able to drive the controller and motor directly without a battery connected.

Hi d8veh did you manage to find out what was the actual problem?

MS.

 

[AndyC1697]

Hi I hope someone can help with a similar problem to those listed in this tread.
I have 2x Snooper fold up bikes with batteries that fit inside the down tube.
One of the batteries is only lasting for a short time and cuts out showing half power whilst the other works as normal on either bike. They have only had about 12 charges and are unfortunately 18months old.
The importer says that he is not likely to have any more and does not have spares!.
The batteries are 24v 8.5 a/284 Wh, Li-ion Polymer. Model YSH-LDC-02.
From what I've read, it would seem maybe that one of the cells is not charging.
Does anyone know of a company to repair/referb the battery?
The supplier suggests I send the bike back but is unsure what they will do, so I'm thinking that I will be left to sort it out myself.
On the bench both batteries show 56v but it will be difficult to see what they show under load as I'm not sure I can get to the wireing

 

[alienonline247]

I'm having this exact problem too. Anytime if I climb a steep road, it climbs fine with power but then after few minutes even after being on flat road the motor starts to stutter/jitter/like on and off/losing that constant power. The problem sort of goes away by itself by passing of time. My bike is 250watt bafang 36volt. It never use to happen with the battery it came in with 8.8ah. However, that battery was lost so I bought another battery 9ah from different vendor. With this new battery when this happened I thought the motor or controller was broken. I parked the bike and then it started working just fine next day. So I started blaming the battery for it. I always considered that the battery was at its end when this motor stutter happens because there mustn't be enough battery left. It was always confusing for me because sometimes the motor would start cutting out after long ride and sometimes after short ride so I was always surprised why would the battery start to finish so early.

Now I've built a new battery pack of my own 15.6ah and so the same thing happening with this battery so now I became skeptical that it's not the battery! I contacted the vendor where I bought the kit from and informed them of it. They told me if the current is too high this would happen and it could burn my motor or the controller. They told me to upgrade to more bigger motor/controller or pedal up when on hills. Keep note that if I always use half throttle it keeps going without any problem. So I've decided to keep using by using half throttle to keep the current less. It works fine this way.

Hope it helps understand the problem to someone.

 

[Deleted member 4366]

It sounds like a controller fault or a motor connect issue. Did you check the motor connectors at the controller end? Which controller is it? Can you show a photo of it and it's connectors?

Batteries don't make the motor stutter. When bad, they normally just cut out completely for a while.

 

[anotherkiwi]

I'm glad it's sorted now.
The controller can take it. It has built in thermal protection and over-current protection. My hills are worse than yours, and I've never had a problem.

Today I experimented with that for the first time, a 15 A KT controller can handle >600W for about 30-45 seconds then it throws the switch...