How Do I Find This Connector?

mattthemuppet2 said:
a closed short would be dead easy to find - there'll be a bright flash, an after glow and then the smell of burnt metal and plastic :) The batteries are very well spot welded together. The problem came from the battery protection board on the top. If it gets disconnected from any part of the battery (there are connections to each bank of four cells) then it permanently shuts down the battery and it won't turn the bike on. The wires at the top that you can see coming from the battery go to another 10 cell battery piggybacked onto the battery board to trick it into thinking it's all connected. However, when I reconnected one of the banks to the protection board (pulling out the piggyback wire VERY carefully at the same time) I must have made a cold joint that looked good, seemed good, but then opened when I was finagling it back into the case. Joint opened, protection board thought that one of the battery banks had disappeared, pack is bricked.
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Can't tank a bank.
I had to say it. :grin:
 
Those ebike packs are pricey! Recently, I just went with the cheap ones from China. Could you just replace the BMS on that pack?
The issue with building my own 3.7v pack is that I also need over discharge protection. I was considering using a protected 18650 cell but they are 70mm long and I can't find a battery holder for those. Seems like a silly problem but I don't have a 3D printer. Furthermore, I need this in 11 days!
 
Unfortunately the BMS is integrated with the bike - it talks to the motor controller and that tells the pack to switch on.

As for regular 3.7v pack protection you can get those all day every day for little money. They all have the same over charge and over discharge limits, you only have to pick the over current limit for your application. Eg if your heaters pull 2A, then one of these would work nicely: https://www.google.com/url?sa=t&sou...AQFnoECBYQAQ&usg=AOvVaw3JbuUAb2sV40zUuSxFWvtU
 
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The heater draws 600 mA. That could work fine. Hey, is an 18650 cell waterproof?
 
You know....I just realized this whole scheme is not gonna work. :( If I build a sealed black box with wires and cylindrical objects inside, there is no way this is going to be able to get on an airplane! Li cells cannot go in the checked baggage and TSA is not going to allow some home made device that looks like a bomb under x-ray. Right?!
 
You are actually advised to carry LiPo batts in your carry on now. I guess the flight attendants have Class D fire extinguishers in the beverage cart?
 
pontiac428 said:
You are actually advised to carry LiPo batts in your carry on now. I guess the flight attendants have Class D fire extinguishers in the beverage cart?
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Yes. My brother just did this with ski boot heater batteries. He appropriately put them in his carryon and TSA examined them and determined what they were. I don't want to spend an hour at the checkpoint explaining that my sealed box is a home built ski boot heater system. They may or may not let that on the plane.
 
When TSA sees your battery pack, they'll bow down. When I go through, they all bow down...

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rwm said:
The heater draws 600 mA. That could work fine. Hey, is an 18650 cell waterproof?
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that's a lower power draw than I expected, you'll be able to find others with 1 and 2A cut offs that might be better/ cheaper. I've used a load of the little all in one boards with micro USB charging ports, they're dead handy. If it were me, I'd cut off the plug from your other pack, get a protection board (I should have a spare), wire up a couple of li-po cells from yours truly and dip the whole thing bar the microUSB port in plastidip. That'll work just fine, promise.
 
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