CONTROLLER

OK,
I charged the battery. It has a power indicator on one end. Push a little button and it has four lights. Only three light up, even when fresh off the charger. Is this an indication the battery is bad or going bad?
 

indianajo

Well-Known Member
Probably. At last, some data. I really suggest you buy a DVM from a reputable vendor like newark.com or digikey.com or parts-express.com. Get alligator clip leads on the same order, save freight. (although you can get two packs at the auto supply). BTW dorman meters at the auto supply might be okay, also. Especially high end auto supplies like oriellys or NAPA. I have bought real garbage at Auto-zone & Advance Auto.
There is a thread here under maintenance showing the % charge tables for various voltage batteries. Installing new parts on an undiagnosed problem that could be in any of 3 places is a waste of resources. Particularly since batteries are a $200-800 component. The two $300 ones I bought were garbage. Lunabikes.com sold me a good battery, but they are generic and may require electrical adapter jumpers and a mount to fit your bike. You can see the luna battery left, mounted on an aluminum frame I built on the front of the bike.
If you live in Ohio, Las Vegas NV or Los Angeles, you can get your old battery repacked with new cells. they might also test it for a fee. See the sticky thread up top of maintenance for details. You have to drive your battery there, you can't ship it.
 
Last edited:
Probably. At last, some data. I really suggest you buy a DVM from a reputable vendor like newark.com or digikey.com or parts-express.com. Get alligator clip leads on the same order, save freight. (although you can get two packs at the auto supply). BTW dorman meters at the auto supply might be okay, also. Especially high end auto supplies like oriellys or NAPA. I have bought real garbage at Auto-zone & Advance Auto.
There is a thread here under maintenance showing the % charge tables for various voltage batteries. Installing new parts on an undiagnosed problem that could be in any of 3 places is a waste of resources. Particularly since batteries are a $200-800 component. The two $300 ones I bought were garbage. Lunabikes.com sold me a good battery, but they are generic and may require electrical adapter jumpers and a mount to fit your bike. You can see the luna battery left, mounted on an aluminum frame I built on the front of the bike.
If you live in Ohio, Las Vegas NV or Los Angeles, you can get your old battery repacked with new cells. they might also test it for a fee. See the sticky thread up top of maintenance for details. You have to drive your battery there, you can't ship it.


I have a couple of volt ohm meters. One very good one. Sorry to imply I don't. I'll check the voltage. Since I work on a strict budget I'll have to look for a battery around 200. to 250. The one I have if it's bad lasted almost four years. I'm tempted to buy another.
 

Thomas Jaszewski

Well-Known Member
I recently exchanged emails with a family that bought a budget battery and had a fire. They lost everything. Of course, there's no way to determine what they may have done to help create the perfect storm. If you were involved in battery building and repair and saw some of the builds I suspect you'd run from a $200 battery. But I do get that you need to budget. I'd save up until I could purchase a battery that will hold up and be safer.
 
Good morning Thomas,

Here's what's going on. I took the bike and my dog for a ride a few minutes ago. Before I went I checked the voltage, 45.5 volts. Went about a mile and a half, mostly flat. When I came to the slight hill leading to my driveway, (peddling my ass off) it quit at the top so I coasted down my driveway to park. Checked the voltage. 25.5 volts. Looks like the battery is shot, agree? Most of the ones in my price range go up in price as the Ahrs goes up from 10, to 13, 15, etc. I can't complain, the battery is three years old. Let me know what you think about the voltages. Thanks again,

Charlie
 

Thomas Jaszewski

Well-Known Member
Before I went I checked the voltage, 45.5 volts.
Was this a "full" charge? Regardless, 1.5 miles and a small hill wouldn't use up that much of a good battery.

Taking the pack down to 25.5V is a bit concerning. The Low Voltage Cutout is typically a higher voltage. Running the battery that low often can seriously affect batteries useful life.
 

harryS

Well-Known Member
Crazy numbers, Charlie for a nominal 36 volt battery. Maybe your volt-ohm-meter needs a new battery too.

A 36V battery is no higher than 42.0 volts at full charge, so 45.5 is wrong. The motor controller will quit working at 30 volts. Not to say that your battery didn't drop below that, but that's a lot.

Anway, the overall behavior, battery flat after 1.5 mile of riding does say it's time for a new one. If this same battery let you ride around Tennessee when it was new,, then a new one would work, but even Voilamart says you need more than that.