Trading 18650 cells proposition

Hello all, I am back after a month hiatus.

Story time:

I currently have an electric bike, and I have two battery packs:

One battery pack is a 52v, 20AH battery made of old laptop cells

The second one is a 52v, 8AH battery made from old power tool cells

Here's the problem:

My battery pack made of old laptop cells only lasts about 8-10 miles. Why so little range? It's because laptop cells are not designed for high continuous discharge rates. Meaning that the cells sag in voltage like mad until my controller cuts off the battery pack prematurely.

My second battery pack made of old power tool cells doesn't sag very much, but the problem is the capacity is very low. Meaning I still only get about 10 miles out of my pack made of power tool cells. The power tool cells I typically recover usually only have a capacity of 1000-1500mah, meaning that pack uses low capacity cells.

Time to do something different then.

Currently I am aiming to build an 84v battery (yes my hub motor can handle it, leave that out of the equation). This battery will be a 23S7P battery pack and thus will require 161 cells. Since I want to have a range of AT LEAST 20 miles, I will have to use high discharge (at least 10 amps continuous) AND high capacity 18650 cells to achieve this.

What we know so far:

I can't use laptop cells because their discharge rate is too low.

I can't use "cheap" cells from power tool batteries because typically the only cells I find have a capacity of 1000-1500mah.

This limits my options severely for sources for high discharge cells that are 2000mah or above. My only option is pretty much:

1. More expensive power tool battery packs. A good example is recently I found a Ryobi OP4051 battery pack that contained LG HE4 2500mah 20A 18650 cells inside and I recovered a total of 20 cells. Great, but i'm gonna need a lot more.

2. Hoverboard batteries. Hoverboard batteries typically contain 2000-2200mah 18650 cells that have a maximum continuous discharge rate of 10 Amps, and this should be okay for my project as well. If The hoverboard battery deal was still available from alarmhookup, I would just buy 10 of those and call it a day, but I can't do that because that deal is no longer around.

Here's where you guys come in. I'm asking for the forums help here, and even you can benefit from thisas well.

Many of you guys like me, are opening up power tool battery packs and some of you guys are recovering cells that are 2000mah or above AND high discharge. Then you take that power tool cell you just recovered that was above 2000mah and install it in a powerwall. That cell will likely never see over 500ma continuously when installed in your powerwall, meaning the cell is heavily underutilized.

Me on the other hand, currently have access to medical battery packs with cells at or above 2000mah around my local scrap yards, but they have a very low maximum continuous discharge rate of maybe 5 amps. I can't use these cells, but the powerwall builders on this forum can.

Here's the offer:

If you send me a single high-discharge 18650 cell that has tested to be at or above 2000mah (a cell that tested in at 1800mah or above may also work), I will trade you TWO low discharge cells that have been tested by me to be at or above 2000mah with my foxnovo digital charger 4S at 1 amp.

Ultimately, you will win because if you trade me 50 high discharge cells, you will now receive 100 cells of at or greater capacity but rated at a lower discharge rate. But this doesn't matter to you because your cells are going in a powerwall.

I will receive those 50 cells and can then use them in my ebike battery, while I can't use those low discharge cells.

In this situation, everyone wins. You get more cells of at or greater capacity, and I get high discharge cells.

I'd like to keep this trade to anyone in the lower 48 states in the US, since shipping lithium batteries is likely going to be very cost prohibitive for both parties.

Also, if anyone can just link a place where I can pick up some hoverboard battery packs for 1-$1.5 a cell, then we wouldn't even have to go through all this. There is currently a listing on ebay for some electric skateboard batteries, but the problem is the cells inside are BFN (chinese brand) 18650 cells with a completely unknown continuous discharge rate, so I can't use those until I get ahold of the cell datasheet. If I buy a bunch of those cells and they are only rated for a maximum continuous discharge rate of say 5 amps, then the cell will sag in voltage like mad and we will be back to where we started.

https://www.ebay.com/itm/Lithium-ba...1?_trksid=p2349526.m4383.l4275.c10&rmvSB=true

Any help would be appreciated.

I can't interest you in any LiPos can I? All high discharge (5-10C) and 12000-15000mAh) The packs below have mostly been dismantled - good cells kept and tested and puffy cells recycled. I have a steady stream of these coming in - sometimes they are already in a 23s config and only 1 or 2 cells are dead.







I also have some high drain 18650s....I have several packs ofLGDBHE21865 that so far, have been testing at around 2200-2300. I have 2 'blocks' of 50 cells already (still)wired up with nickel strips in a 10s5p config.

Grumplestiltskin said:

I can't interest you in any LiPos can I? All high discharge (5-10C) and 12000-15000mAh) The packs below have mostly been dismantled - good cells kept and tested and puffy cells recycled. I have a steady stream of these coming in - sometimes they are already in a 23s config and only 1 or 2 cells are dead.







I also have some high drain 18650s....I have several packs ofLGDBHE21865 that so far, have been testing at around 2200-2300. I have 2 'blocks' of 50 cells already (still)wired up with nickel strips in a 10s5p config.

Click to expand...

The lipo packs *may* work, but the LG HE2 cells would really be what i'm going after. Since I am building a pack with 161 cells, I would need 4 of those 10S5P configs to break down and rebuild into my battery pack. If you don't have enough cells that fine, I was planning to mix and match cell brands and capacities to begin with. I'll take what you've got.

The reason my interest wanes for "pouch" style cells is because this battery pack I plan to build will be triangular-shaped. cylindrical cells are an easily way to maximize every available centimeter of space available to me while lipo cells wouldn't really fit correctly. Lipo cells also require compression and cell padding, while cylindrical cells do not. Remember, my priorities are much different than a powerwall builder who is okay with using a little extra space. I need to use all the space I have .

Let me know whether you would want to do a trade or if you just want money. I don't know whether you are planning to use these for your own projects or just reselling them. I'll send you a PM.