Upgraded to lithium issue

bmurph44

New Member
Region
USA
36 volt EV Global......I just upgraded to lithium, at low power all is good but if I switch to high power after a few seconds the bike shuts down then a minute or so later it will turn back on, the battery I bought is in the link below. Anyone have an idea of what may be causing this to happen.

 

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Unless defective, the battery has a low maximum current output. At that price with no name cells that's what you're going to get. Also an issue with small batteries/big motors. Which exact battery did get?
What's the power rating of your motor?
 
Unless defective, the battery has a low maximum current output. At that price with no name cells that's what you're going to get. Also an issue with small batteries/big motors. Which exact battery did get?
What's the power rating of your motor?
I bought the 36 volt 10AH, I have no idea the motor power rating.
 
Well that's your issue.
10ah is on the small side of batteries and if not made with some of the higher end / high discharge rate cells, a big motor is going to overwhelm it.
I have a 10ah battery made with Sanyo GA cells and it can put out 30a continuous. But that battery was $375
Knowing your motor wattage is important when selecting a battery.
 
Looks like you have an older ebike that used lead acid batteries, and you bought a 36V 10AH battery in a green shrinkwrap from amazon? It shuts off under high current, buit works on lower power.

The amazon ad's smallest battery is 36V12Ah with a max current of 15A. It can probably do a bit more more than 15A, even for a $120 battery, Looking at your bike, it seems like this should be enough to cruise around up to 16-18 mph, if the battery is healthy.

What were the older batteries? Were they 24V or 36V? I'm asking to rule out the possibility the controller in your bike is speed limited, and shutting down.
 
Does the bike beep before it shuts down? That bike speaks Morse code.


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There should be a sticker on the motor with the wattage rating. That’s definitely a 36v bike. The 24v versions came in black and red. I have a 24v black version.
 
.. _ _ .. _ . _
or
It states 36v right on the bike. 🙃

Quick Google comes up with 500w motor.
The battery "should be adequate" with stated specs but there's very little quality or control of in a battery at that price.
 
Sounds like the controller or battery's bms is shutting the thing down. The controller could because of low voltage on heavy loads, the bms because of low voltage of a group, or too high of amp draw. I'd go with the controller shutting down from a low voltage. Did you reset your controller's battery voltage limit to your new battery's chemistry?
 
If you follow the wires from the motor... It'll lead you to the controller.
On a bike this old I'm not sure if it has adjustable settings. @Slaphappygamer?

Did you try contacting the seller?
 
If you follow the wires from the motor... It'll lead you to the controller.
On a bike this old I'm not sure if it has adjustable settings. @Slaphappygamer?

Did you try contacting the seller?
No settings a user can change. Just the “Eco/Norm” switch. The seller is long gone. This bike is from late 90’s. OP probably already saw, but here is the manual.

Kind of sounds like voltage sag that is disabling the bike. Though, a sound should be played to indicate low voltage warning. Perhaps voltage sags so fast that LED codes aren’t displayed.

Do you have a way to quickly check pack voltage after the bike shuts down.
 
No settings a user can change. Just the “Eco/Norm” switch. The seller is long gone. This bike is from late 90’s. OP probably already saw, but here is the manual.

Kind of sounds like voltage sag that is disabling the bike. Though, a sound should be played to indicate low voltage warning. Perhaps voltage sags so fast that LED codes aren’t displayed.

Do you have a way to quickly check pack voltage after the bike shuts down.
According to the Amazon description the battery has a 15a continuous output. If regulated by the BMS it may be the battery itself shutting down.
I agree I would test the battery output immediately after shut down to verify who is shutting down, controller or battery.
But in the end there is no remedy unless the seller agrees that the battery is supposed to be able to handle the load without issue and replaces and/or upgrades.
A small battery requires quality hi output cells and a matching capable BMS to work in a hi draw application like an ebike.
These batteries seem better suited for autonomous vacuums which the reviews seem to indicate to be the typical buyer.
 
I can’t imagine that this new lithium battery has worse discharge than 3 12v SLA. Stranger things have happened.
 
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