Battery compatibility question

tego

New Member
Region
Europe
Hey everyone,

I'm a pretty decent home mechanic, but very new to the e-bike world. I bought a conversion kit off eBay recently without really doing my homework beforehand. The battery pack it came with doesn't inspire any confidence now that I've read more about them, so I'd like to return it and buy a better, safer one with cells made by a reputable manufacturer.

This is the one I'd like to get (48V 13.8Ah). It comes with either Sanyo/Panasonic NCR18650GA or Samsung 1865035E cells.

Kit information:
  • Bafang 48V 500W rear-hub motor.
  • No-name 48V 17.5Ah battery, with Luhua 18650 2500mAh cells and XT60 connector.
  • I know nothing about the controller, but here's a photo of the front plate, I'm sure you'll understand the numbers better than I do.
Am I right in assuming I can purchase the battery I linked above, together with an Anderson PowerPole to XT60 adapter, and simply switch the batteries? Or am I missing some compatibility issue? I would of course also buy the dedicated charger and mounting hardware.

Thanks a lot!
 
Under US law you are not allowed to return a lithium ion battery over laptop size without being a certified HazMat pack agency. I don't know European law but they are usually more stringent than the US.
You are allowed to drive it in your car to the place you bought it from if they will take it back.
I load test batteries for bikes. Simpler than mounting it on the bike. For a 48 v battery takes 15 ohms 250 watts resistors to do a 3 amp test. 10 ohms 400 watt resistors to do a 5 amp test. Do this outside on concrete not indoors. Using alligator clip leads hook the battery through the resistors + to -. Measure the voltage with other clip leads with a DVM continuously. The time to go from 54.6 (full charge) to 46.8 (50%) time the amps gives you amphours of 1/2 your battery.
My **** batteries from Amazon btrbattery and ebay sun-ebike baldwin city warehouse collapsed voltage immediately after I hooked up the load. The Amazon would stay 7 v and I got my money back. The Ebay one would return to full voltage as soon as a load was off it, so I took more than 31 days to prove it bad and I didn't get my money back.
If a battery passes that low amps test it still might not deliver the 15 or 20 amps required (legal watts/48 v). A 20 amp test would require a 2.5 ohm resistor of 1200 watt capacity. I didn't have to do that because my **** batteries had bad connections. A battery could be properly connected but made of flashlight cells, for a amp capacity of 1/2 * number of stacks.
If the battery I had bought was performing okay and has adequate capacity and amp delivery I would use it until it didn't. You have to pay the disposal fee whether you use it or not.
Best of luck
 
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"Under US law you are not allowed to return a lithium ion battery over laptop size without being a certified HazMat pack agency."

I don't believe this is true. There may be a extra charge for shipment and you are required to label it as a battery,I think , but you don't need a license of any kind.
Edit: To be clear the shipper should be able to provide HazMat packaging.
 
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Hey everyone,

I'm a pretty decent home mechanic, but very new to the e-bike world. I bought a conversion kit off eBay recently without really doing my homework beforehand. The battery pack it came with doesn't inspire any confidence now that I've read more about them, so I'd like to return it and buy a better, safer one with cells made by a reputable manufacturer.

This is the one I'd like to get (48V 13.8Ah). It comes with either Sanyo/Panasonic NCR18650GA or Samsung 1865035E cells.

Kit information:
  • Bafang 48V 500W rear-hub motor.
  • No-name 48V 17.5Ah battery, with Luhua 18650 2500mAh cells and XT60 connector.
  • I know nothing about the controller, but here's a photo of the front plate, I'm sure you'll understand the numbers better than I do.
Am I right in assuming I can purchase the battery I linked above, together with an Anderson PowerPole to XT60 adapter, and simply switch the batteries? Or am I missing some compatibility issue? I would of course also buy the dedicated charger and mounting hardware.

Thanks a lot!
As long as you match the voltage and amps of the battery with the controller,(that came with the kit), you should be fine.

As a side note, be sure to follow safe charging and storage practices. Get a chemical rated fire extinguisher and keep the battery pack away from flammable materials. I keep a wool blanket along with the fire extinguisher.
Not to scare you, but better safe than sorry.
 
As long as you match the voltage and amps of the battery with the controller,(that came with the kit), you should be fine.
The voltage is the same. The product page says it can provide a "maximum continuous discharge current" of 25A. On the controller it says "current-limiting" 18±1A, so I guess it means it can draw a maximum of 19A? So that means the battery can take it, right?

As a side note, be sure to follow safe charging and storage practices. Get a chemical rated fire extinguisher and keep the battery pack away from flammable materials. I keep a wool blanket along with the fire extinguisher.
Not to scare you, but better safe than sorry.
Yep, definitely. I have a big ABC extinguisher close by (which seems to be enough according to the internet), and the battery is as far from any flammables as possible. Thanks for the advice!
 
@JES2020 Unfortunately @indianajo has a point about the shipping regulations. I checked now, and for example with the Austrian Post you're not allowed to ship batteries that exceed 100Wh. They even give E-Bike batteries as an example of what you're not allowed to ship. If my math is correct, this pack clocks in at a whopping 17.5Ah * 48V = 840Wh.

The eBay seller sent the battery via UPS. I checked their requirements too, and this is what they have to say about batteries over 100Wh (DeepL translate from German):
You need a UPS contract for dangerous goods. Packing according to **UN specifications, class 9 label as well as transport papers and package markings for dangerous goods are required. For further details please refer to please refer to the IATA regulations: http://www.iata.org/
Problem is, the box they sent the battery in (which I still have) has f*ck-all markings on it or any special packaging inside, so I highly doubt UPS even knew what they were transporting.
 
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If you learn how to solder, you won't have to worry about adapters. And if you're going to DIY ebike, better learn how to solder.

Here in the USA, there's a $50K federal fine if they catch you shipping lithium without the hazmat stickers, and the necessary permits to apply them.
 
The voltage is the same. The product page says it can provide a "maximum continuous discharge current" of 25A. On the controller it says "current-limiting" 18±1A, so I guess it means it can draw a maximum of 19A? So that means the battery can take it, right?


Yep, definitely. I have a big ABC extinguisher close by (which seems to be enough according to the internet), and the battery is as far from any flammables as possible. Thanks for the advice!
Yes you are fine with the amps.
I find it hard to believe that a UPS contract is much more than filling out some paper work.
I mean with all the Ma and pa battery shippers online, but I will call Fedex on Monday for my own information.
 
Thanks a lot for your help, everyone! I ordered the battery, and I'll post an update once I get a resolution on the return of the old one.
 
So , you absolutely can return your battery, you just have to use a certified packer. like :
I knew it couldn't be so complected as requiring YOU to get certified.
 
In the meanwhile, the on/off switch on the battery stopped working. Now it's powering everything all the time, no matter which position the switch is in, whereas before it used to shut everything down. So it's no longer just a shitty battery pack, it's a shitty battery pack with a defective electrical circuit. Joy.
 
In the meanwhile, the on/off switch on the battery stopped working. Now it's powering everything all the time, no matter which position the switch is in, whereas before it used to shut everything down. So it's no longer just a shitty battery pack, it's a shitty battery pack with a defective electrical circuit. Joy.
Who did you buy it from and did they offer free returns?
 
Returns are always free here, it's EU law. I bought it off ebay.de from a Chinese seller, but the kit shipped from Poland, so they have to abide by EU regulations. They've already offered to do so. It's not the cost of the return that's an issue, it's the liability for shipping Class-9 materials without the proper precautions. Most couriers won't let individuals like me ship anything anything above 100Wh. UPS will do 300Wh, but that's still way below the 840Wh of this battery, and no one will handle defective batteries. I guess there might be special handlers here too, like the one you linked, that might accept the package, but really that's up to the seller to arrange, not me.
 
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I ended up with a free 48v 15ah battery because of shipping restrictions. An Amazon end order error, China based seller with US stock. They just gave it to me rather than try to have it returned, maybe same will be for you. At the time I had no need for a 48v battery but since then I have and it has been a great battery.
 
Returns are always free here, it's EU law. I bought it off ebay.de from a Chinese seller, but the kit shipped from Poland, so they have to abide by EU regulations. They've already offered to do so. It's not the cost of the return that's an issue, it's the liability for shipping Class-9 materials without the proper precautions. Most couriers won't let individuals like me ship anything anything above 100Wh. UPS will do 300Wh, but that's still way below the 840Wh of this battery, and no one will handle defective batteries. I guess there might be special handlers here too, like the one you linked, that might accept the package, but really that's up to the seller to arrange, not me.
Sounds like you're all set then.
BTW the shipper I posted is international.
 
I don't believe this is true. There may be a extra charge for shipment and you are required to label it as a battery,I think , but you don't need a license of any kind.
Edit: To be clear the shipper should be able to provide HazMat packaging.
WRONG JUST WRONG
I took the course and was certified.

"According to the DOT , anyone involved in the manufacturing, packaging, preparing, and shipping of lithium batteries must receive comprehensive safety training."

UPS Customers wishing to transport damaged, defective or recalled (DDR) batteries must be pre-approved by UPS. UPS only accepts DDR shipments via Ground Continental U.S. Service in special permit packaging designed to contain a thermal event.
 
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