Where to go with RabbitTool gone?

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I think the PTB option ok but you still have to add $350 for the controller. With that investment, buying a Blacktip make more sense. What I'd really like to see is an inexpensive used unit, maybe from someone who did an upgrade to LiPo and has a perfectly good batt pak just taking up dust. (like any of that is going to happen.)

NiMH ages just like lithium chemistries though, so even if it was "perfectly good" when it left, it's not necessarily perfectly good anymore... Also you can DIY with the controller from the Blacktip for about $100 if you can solder

Also you can solder NiMH cells, you don't need a spot welder
 
NiMH ages just like lithium chemistries though, so even if it was "perfectly good" when it left, it's not necessarily perfectly good anymore... Also you can DIY with the controller from the Blacktip for about $100 if you can solder

Also you can solder NiMH cells, you don't need a spot welder
When I built a new battery pack, I soldered the connectors. Worked fine as frogs hair.
 
I spent around $500, IIRC, on a lifepo4 battery from Ping for my Sierra as the NIMH Rabbit Tool battery was $850. That was 4 years ago. If the battery on my Sierra died today I'd give serious consideration to selling the Sierra and replacing it with a Blacktip. Total out of pocket would be about the same.
 
I checked with batteryspace. Thank you for the suggestion. While they do offer a rebuild for a cuda 400 for a reasonable price, $400, they do not rebuild a sierra. It's the same pack, just configured for 24V but they don't do it.
 
I checked with batteryspace. Thank you for the suggestion. While they do offer a rebuild for a cuda 400 for a reasonable price, $400, they do not rebuild a sierra. It's the same pack, just configured for 24V but they don't do it.

do you have programmable electronics? If you do, then it doesn't matter, just order the Cuda pack and set up the speeds the same way that they recommend for the PTB conversion
 
I've considered it but I don't have easy access to the machining I'd need to make a new pack and to use the existing package I'd need access to a spot welder. I'd rather by a new pack, a new (used) scooter, or pay to have mine rebuilt.
I made a new li-ion 7s 23ah sierra pack for about $450. You can get handheld spot welders for about $100, cell holders are dirty cheap (<$10). Pretty much any high capacity but low discharge (to save money) 18650 cell will work with a 30amp BMS.
 
Did Jona reach out to you? He posted in a scooter group on FB that he has one NiMh Sierra battery. No idea on the price.
 
$36 spot welder https://smile.amazon.com/gp/product/B08M5GMC33
$7.50 nickel strips https://smile.amazon.com/0-15x6x50mm-Soldering-Capacity-Lithium-Battery/dp/B07PQP55CM/
Mine works great! You just have to make sure your power source can supply a few hundred amps. A car battery will do nicely, as would a good lipo pack from an RC toy. Bench power supply or UPS battery will not work (unless you spent thousands on your bench supply) They cover it in the product instruction manual but lots of youtubers are seen blowing out the transistor by using a power source that's too limited....

I've soldered onto many a cell with a regular iron as others have said. Supposedly you can damage the cell by overheating it, so I bought the aforementioned spot welder.
 
$36 spot welder https://smile.amazon.com/gp/product/B08M5GMC33
$7.50 nickel strips https://smile.amazon.com/0-15x6x50mm-Soldering-Capacity-Lithium-Battery/dp/B07PQP55CM/
Mine works great! You just have to make sure your power source can supply a few hundred amps. A car battery will do nicely, as would a good lipo pack from an RC toy. Bench power supply or UPS battery will not work (unless you spent thousands on your bench supply) They cover it in the product instruction manual but lots of youtubers are seen blowing out the transistor by using a power source that's too limited....

I've soldered onto many a cell with a regular iron as others have said. Supposedly you can damage the cell by overheating it, so I bought the aforementioned spot welder.
Or even cheaper.
Portable DIY Mini Spot Welder Machine, Kecheer 18650 Battery Various Welding Power Supply for Super Capcitor - - Amazon.com

These dont have a delay between the probes contacting and the current applied which is a nice plus but you'll pay for that. In any case, the OP can get a range of simple DIY grade spot welders for very little up to $1000s depending on features.
 
https://www.shearwater.com/products/perdix-ai/

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