Cyclotricity Battery Issues.

[Teab8g]

I'm having issues with my ebike battery. I am only getting around 10 miles out of it before it die's before 40-50 miles wasnt uncommon. I spoke to Cyclotricity that suggested that I run it compleaty flat and then do a 12hr charge on it 3 times and that will sort it out.

Does that sound true or compleat bull too get me off the phone. Iv'e not found there tech support to be much use in the past so its got me thinking. Bike is around 13 months old and battery has done 2k miles. I had the rear motor changed out around 1500 miles as it kept cutting out.

 

[Nealh]

Could be out of balance.
We need to know the voltage after you have charged it and the batteries nominal voltage.
Depending on the reading you may have to open the battery to check cell groups via the BMS if fitted.

 

[Deleted member 4366]

That's what you'd do if it were a nihm or nicad battery, but it isn't. It's a li-ion one, so that won't do anything except maybe make it worse.

First thing is to fully charge it. when the charger goes green, take it off and measure the voltage directly on the battery terminals immediately. That will give the first clue as to what's wrong. Let us know what that measurement shows.

 

[Teab8g]

Ok sounds like i have some reading to do to lean how to do that.

also while I'm typing a small update on traveling home tonight. It died again the LCD said that the battery was flat however the actual battery pack was showing 3 of 4 bars. Turning the battery off and on I managed todo another 5 miles on battery alone with no pedaling ( not how i normally ride ) and the battery pack is still showing 3 bars. So now I'm really confused.

 

[Nealh]

A couple of possible faults I can think of but without confusing the issue for now we just need a charged voltage reading.

 

[Deleted member 4366]

You have to measure and test things so that you can home in on the cause and eliminate possibilities along the way. That will lead you to a solution. If you start guessing and jumping from one thing to the next, you might get lucky, but the probability is that you just end up wasting time.

 

[Teab8g]

Ok so i measured the battery. I set the multimeter too 200v and got a reading of 42.0 back. Whats the next POA ?

thanks for the help.

 

[Nealh]

42V is perfect for a 36v nominal battery and indicates serial connections and overall balance is fine, though it doesn't rule out that some parallel cells/connections may be low or failing which would account for poor range.
You haven't mentioned the motor wattage or battery Ah and which power settings you use.

 

[Deleted member 4366]

Ok, now we need to know exactly what battery it is because Cyclotricity use several different ones. Please show us a photo.

 

[Teab8g]

It's the 15ah 36v one. Also it's the 500w motor. Haven't got a photo on me just yet but can get one later tonight if needed.

Also just like to add some info I've worked out. The LCD is saying the battery is dead and turning off. However the lights on the side of the battery still indicates 3of 4 bars remaining. It also turns off on the exact same place twice in a row. Going up a steep hill. Making me think that the battery isn't sending enough electricity quick enough and thus cutting out?

 

[Deleted member 4366]

We need a photo.

 

[Teab8g]

Photo attached

 

[Deleted member 4366]

Have a look at all the controller connections first. Unscrew the 4 screws in that nlack box under the battery. Have a look at all the wires too. It's very tight in there so some wires might be squished. Check that the two battery ones are tight and clean, then follow the LCD wite all the way vrom the controller to the LCD to make sure that it's not been damaged by a too tight cable-tie.

 

[Teab8g]

Been a while. Basically it's the Bms that's faulty ( ended up sending the battery to cyclotricity) they are saying that's its not fixable and are trying to sell me a replacement battery.

Anyone know if this is true or is it going to cost me a few hundred to replace the battery.

 

[PH001]

The BMS and the battery are in the same case so if you get a new battery it automatically includes a new BMS. Incidentally I had exactly the same problem with my Stealth battery at 11.5 months and Cyclotricity diagnosed the same thing (faulty BMS). I would have loved to have taken the battery apart and inspected exactly what the issue was but alas this would have invalidated my warranty. Thread is here... (post #121) http://www.pedelecs.co.uk/forum/threads/cyclotricity-stealth-owners-thread.24473/page-7

Fortunately for me I did report the issue just before 12 months so although it took them almost 6 weeks to respond they did send me a new battery under warranty.

 

[Deleted member 4366]

Those batteries are a bit under-rated for 500w and 1000w applications. I estimate that they'd last less than a year if uses regularly. If yours has lasted beyond the warranty period, you've done pretty well. You bought a cheap kit. That's the downside. You really need a battery with high discharge cells, like Samsung 30Q. I'd cut my losses and get one from Eclipse or somewhere else. They have the same type of case, so plug-and-play. Plus, you get a spare mount, so you could use the battery on two bikes.

 

[Teab8g]

If only I'd have read that sooner. I've ordered a replacement from them. £264. To be honest I'm going to be using the bike a lot less next year as I'm moving further from work. They are sending me the old battery back he said the cells are fine and still worth something.

As I understand it the cells are completely fine it's the BMS that's fubard. I have no idea what that means Tbh but I'm sure it's worth something to someone?

 

[PH001]

The BMS is what monitors and controls the charge and discharge of the batteries (BMS stands for battery management system). I have to agree with what d8veh says, I think the batteries are a bit pushed which is why I'm running mine at 250W for the forseeable.

The BMS failure is something I'd love to investigate but until then all we can do is speculate. It's a little odd in that mine still seemed to charge OK but it just lost loads of range and capacity. Almost like the batteries were going higher and higher impedance. I'm not 100% convinced by Cyclotricity's story if I'm totally honest.

 

[Teab8g]

Yea my issue was weird. The battery indicator was showing a full charge but under any strenuous load ( up hills) it would just die. Crest the hill turn the battery off and on again it would be fine.

 

[Wheel-E]

Their QC could do with a bit of work. My brand new battery arrived with blown fuse and wires pinched in the case when it was closed at the factory. I called and they offered me the choice of opening and repairing myself without affecting the warranty or sending it back. Also notice the sliver of plastic hanging off the case in the second picture.

Can you not get hold of a new BMS, then you'll have two batteries? I have other photos of the inside and it shows a very small circuit board.