Reviving a Green e Wheels bike

[robby986]

I bought a bike from joe at green e wheels, now defunct, I think, in Melbourne Australia about three years ago. Used it to commute to work with it. It is a 36 volt system and it went quite well for a time until it stopped. I had it repaired and replaced the 13 amp 36 v li ion pack that didnt work with a 10 amp 36 volt battery which worked for a time but then succumbed to the same problem the motor cut out and would not go. I went back to using a much better and engineered technology -2006 Prius i tech. 106000 km -just change the oil! In the meantime I have lurked on the forums and hopefully educated myself a little and went back to looking at my sad e bike. I diagnosed part of my problem to a suspect power wire and made the motor run but it still cut out way too early. I mounted a multimeter on it and saw that the lvc in either controller or the bms was the culprit. Solution -buy ping 15 amp 36 volt pack with upgraded 5 amp controller and no voltage sag. Job done. I made a mock up of he ping, fitted a box on the rear of the bike and bought a cheap back pack to put he Ping pack in, but something was nagging at the back of my mind. If i bought the Ping i am sure that it would work, but I would still not undrrstand it. Just like my Green E wheels bike.

I have a Walkera lipo powered helicopter and was looking for some new lipo batteries and somehow or other fell over the hobby King site. What a revelation- Turnigy 5s 5000mah batteries x 4 3010b icharger, cables Turnigy watt meter p350 power supply paraboard all ordered on the internet and on the way to my place. This charger looks like it can charge anything and 30 amps- wow. Anyway i know that I probably wont be exploring the edge of the icharger envelope with my p350 powersupply but I am still very excited. 5 amps is a very long time to wait. Sorry Ping.
I was in my shed today and now that I know a very little more about batteries I decided to revisit my old allegedly buggered 36 v 10s li ion packs. The 10 amp had a voltage of 40.1 volts and it was made up of 10 cells in series with half the cells at 40 volts and the other at 40.1. i hooked up the 1.8 amp charger and it was happy to cut out and leave the cells at 40.1 volts. Does this sound correct to you experts? The other 36 volt 13 ah pack has 1cell that is reading .7?volts . All the others are at 4 volts. I am going to do two one while i wait for my Hobby King shipment. On the 10 amp pack I am going to remove the bms and use my Turnigy meter to monitor the voltage to see if I can avoid the low voltage cutoff from the bms by jumping or removing the bms and see if it is the controller that is cutting off. On the 13 amp hour pack I would like to see if I can individually charge the low volt cell with my 3010b icharger to get its voltage closer to the other cells or throw it away. I can see why you love e bikes everyone, i think I'm hooked!
Pardon me if I appear a little enthusiastic but for you younger folks I am 59 this year and I am still excited about the way we can learn on the net. I used to have to go to the library. Often someone else had already ordered the book, if it was there in the first place. Now it is on my I pad whenever I want it it. This is the life!

 

[dogman dan]

Chances are, your problem was mostly battery related. But even more common is connectors with bad contact, followed by chargers that seem to work but don't.

I bet your bike will run like a champ on the lipo, and if not, we can help you figure it out. My advice remains primitive, like fixing my car. Sometimes replace good parts one by one, till I hit upon the bad one. :lol: Finally I got a motor and controller tester, but that won't help you test your stuff. Others here can walk you through anything if you can grasp what they say. 8)

 

[heathyoung]

My goodness that was hard to read.

You have one dead cell - these cells are LiCo (lithium cobalt) - you could bypass or remove the dead one, unlikely that you will revive it. If you remove the BMS use something like the Cell-logs with optoisolators to pull your throttle down when you hit LVC.

Depends on your electronics abilities, you can make a LVC pretty easily.

 

[robby986]

Thanks for the help, i desoldered the bms and charged it up and took it for a spin and it didnt cut out until much later, but it still cut out. I suspect it was the 31volt lvc on the controller this time. I am waiting for my turnigy watts meter and i will give it a try to see the lowest voltage to confirm. I think the bms lvc was set at a higher voltage so cut out earlier. I am looking forward to getting the rest of my order from hobby king. I wiil then install my new batteries.

 

[heathyoung]

I'm in the process of setting up LVC with cell-logs at the moment, its working well.

They work best at 6S (even though they are 8S) because the drain on all cells is identical.

 

[robby986]

Sounds like you are a bit ahead of me. I think your idea is great as i am a bit concerned at my controller lvc of 31 v. Ill probably do similar to you. I'm still waiting for my parts.

 

[jateureka]

Be careful with that iCharger 3010B - read the comments on the Hobby King web site, a lot of them went up in flames due to poor design or poor build quality!

 

[robby986]

Thanks for the heads up. I did notice that but decided to take a punt on getting a good one. Without trivializing it i feel like one of the nasa astronauts on the launch pad. I will be very cautious with my first charge, and my second and my third! I was thinking about this the other day when buying a comfort seat and handlebars for my other bike (100 percent sweat wheel) The guy serving me asked about selling e bikes in his store. I answered that reliable foolproof battery technology was what was holding up the take up of e bikes in the mainstream in my experience. I pointed to my Prius in the czrpark and said that they need to operate flawlessly like that before joe public should get his hands on one. We are at the bleeding edge.

 

[robby986]

Received the i charger 3010b and my batteries last Thursday. I had to make up two sets of parrallel xt60 cables with three in parallel and then joined with a series connector. I balance charged the 6x5s turnigy 5amp packs using p350 15v 350wpower supply.i set up a laptop and used the i charger software to log the first charge. I charged to 41.5 volts. It all woked extremely well. The p 350 was using around 21 amps to produce the 15 amps charge. The i charger cut out because the defalt settings in the charger only allowed 5000 ma of charge. I turned this feure off. The p350 was warm to the touch and i could feel no heat in the icharger. All the cells balanced. I decided to do away with the switched key and the built in battery box.I have mounted a milk crate type box on the pack rack and have put the batteries and my turnigy watt meter into a small backpack with a lead poking out of the zip. I put this in the crate with some ocky traps to hold it in. My first two rides went without a problem and i have yet to see the leds on the throttle go below full. Its been two years since i stopped riding my electric bike and, even though it was raining and about 12 degrees celsius i loved the ride. At the end of it my battery log read-Ride to dads short way there and long way back
Battery v 41.4 at start of ride at end of ride 39.83
39.4 Vm 2.662 ah 17.46 Ap 696.2 Wp 107.1 wh. next trip a commute to work 17 km. These batteries feel much snappier than the original battery pack. I am thrilled.