Battery troubles

Barkme Wolf

Active Member
Both the batteries for my Radwagon are on the fritz. One the LCD light went dead but the power works. The other has a full charge but wont turn on, the tail light works though so it has juice. Only had them under 2 weeks.
 
Rad Power Bikes took care of the problem. The one battery that stopped working, worked when I brought it in but they replaced it (had stopped working twice since i got it). The other one was actually in working order, it was just configured differently. On some of the batteries the LED charge light comes on automatically when you plug it in to charge. On the model I have the LED charge light only comes on when you push a little button on the side of the battery to show how much charge it has left. 250 miles in 2 weeks. Thanks Rad Power Bikes!
 
I'm seeming to have battery issues as well. My battery took a spill yesterday and tumbled/slid about 20 feet. I sanded the damage down as best I could and plastidipped the whole thing. The issue is that I fully charged it last night, took it out for a 15 mile ride this morning, peddling on level 3 assist and gear 7 on mostly flat ground with a few hills, and it took all day to charge once I got back. I'm talking over 5 hours. maybe the battery took some damage in the fall? Or is it the weak 2A charger to blame?
 
You might want to ask radrover about getting that battery checked. That does not sound like a light spill. Sanding and coating won't help if there is an internal issue that could cause a fire. I would be very careful charging until it is looked at.
 
@pxpaulx good point.. However Radrover would default to saying mail them the battery for inspection.

I would ask them what the internal resistance or other parameters should be, and then use a multimeter to check.
 
@JoePah That sounds like a good idea. I will get that done.
If you're not sure about checking the battery yourself, very often a local laptop fix-it guy can for cheap, once you have the specs from Rad.
 
@J.R. I'm a certified motorcycle repair technician. Electronics are no problem for me. I just need the specs.

If that is the case, you might find help with that over in the bicycle section of the endless sphere forums - that is a much more DIY oriented (and very active) forum, and the dolphin pack on the radrover is fairly generic and relatively widely used.
 
@pxpaulx Yeah, I'm starting to notice that. I browsed through that forum today. It's definitely for the more DIY crowd. The only reason I didn't build mine was lack of space in my little apartment. I'm planning to take the battery case apart when the new case comes in the mail, so I will check all the readings then with my multi-meter and perform a physical inspection to see if there was any damage done.
 
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I did 15 miles again today with pedaling on Eco setting 2 this time (gear 7) and I'm 3 hours into my charge so far with the light still red. I'm not sure if it's the battery or charger at this point in time. I'm gonna leave on it overnight and hope that it helps remove some of the internal resistance and helps to balance the cells, but I'm pretty sure the charger just drops to a "trickle" charge for maintenance once the light goes green since the block goes from hot to cool.
 
A 2A charger could take awhile.. but 15 miles isn't a lot for that battery pack unless you're riding a lot of hills .If the battery pack is hot to the touch during charging that's not good.

An easy check after you think it's completely charged is to measure the battery voltage hot off the charger (right after it turns green). The expected voltage should be around 54.6V if it's a 48V pack, and the charger is set to 100%.. Some are variable.

http://lunacycle.com/chargers/48v-3amp-ebike-lithium-smart-charger/
 
@J.R. I'm a certified motorcycle repair technician. Electronics are no problem for me. I just need the specs.
That's good! Just trying to offer an avenue to a solution. Many of the folks that come here don't own or know how to use a multi tester. No shame in that. I know a person that repairs laptops and he has broadened his scope of work to include Li-ion batteries from consumer products. I showed him the batteries from my bikes and he's looking into it to see if the ebike battery market is in need of repair techs. It's a great avenue for those that don't have a local ebike shop, or just don't deal with those type of issues.
 
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@J.R. No worries. I checked the voltage this morning when I took it off of the charger. It was just under 54 V. I did a stress test on the battery and motor this morning by only doing full throttle with no pedaling. It was mostly flat with a few hills here and there. I made it 13 miles before battery dropped down to 25% on the on-board gauge and E flashing on the display. The last few miles were windy and I am 180 lbs. I did a mix of pedaling (w/ assist) and motor (throttle only) to get me the last 4 miles home. I just checked it after letting it cool down 10 minutes: 1 bar on LCD "fuel"gauge, red light (25% or less) on at battery, and a little over .5 V when I checked the battery. The motor was hot and the battery warm. It seems like my old Prodecotech Phantom X3 had more range out of it's battery than this one, but it was a 500W direct drive hub motor that would do about 20 mph if you gave it some distance. I don't remember the Ah, but I know the battery chemistry was different. The Radrover definitely has more tourqe with its geared 750W motor.
 
Man, there's something wrong.. Seems like your battery pack is not balanced so the charger shuts off before fully charging..

That kind of range with a large battery a moderate weight rider on flattish ground is pretty bad.

Could be the BMS, or a broken tab from a parallel group. .who knows... time to take it apart, if you dare.....

Good luck.
 
... I'm planning to take the battery case apart when the new case comes in the mail, so I will check all the readings then with my multi-meter and perform a physical inspection to see if there was any damage done.

please post photos ... after you put out the fire (just kidding ... sorta)

but seriously, please post some photos after you split the case
 
@JoePah That's my instinct as well. I hope I didn't get a bad battery or that it didn't get damaged in the spill it took. I will take it apart soon and check everything since my new battery case is in the mail already. I will post pics for you guys that want to see how the internals look.
 
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