How did you get the case “warped”
If that’s the case, I strongly recommend AGAINST attepting to revive it… The filter between electrolytes has already been damaged. Continued usage might result in higher chances of explosion/fire
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Daly is such a perfect size to replace the meepo bms
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I learned this the almost-hard way. 
Cells at 0 voltage that then get pushed into the upside down get pretty hot.
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From what I understood, the cells themselves are inherently dangerous no matter the state of their charge, over or under. It’s the lithium that is dangerous, and having a overcharged/undercharged cell will make it so that the filter film inside the cell damaged in the form of having tiny holes that, following the throughput of electrolytes, grow large. Once these holes are too large, they cause micro-shorts inside the cell, which ignites the chemicals and then boom. Being a 0v cell does NOT help the case.
i thought 0v means there isn’t enough energy for the electrolytes to even gothru the film?
If you’re talking about what I think you are, that’s dendrite formation. Which I’ve read happens anyway over the course of a cell’s life, but is accelerated dangerously when the charge falls outside of the intended range. At which point the metal at the pole dissolved into the electrolyte, and then replates when charged, which creates the unknown condition of the dendritic growth and can lead to internal shorts.
Far as I know, having a dead flat cell or battery just sitting about isn’t actively a danger. At least not in the same way that an overcharged battery would be.
If your pack is at 0v the damage has already been done. Now it’s just the chemicals working their magic
I’m not saying it’ll be like a “get to 0v then immediate boom” thing, i’m saying the likelihood of it going boom gets greatly increased
No clue, it just doesnt lay flat. Nothing crazy but definitely some movement.
As I understand it….
- There’s no metallic lithium in rechargeable li-ion cells so we don’t have to be concerned about anything related to that.
- Discharging a li-ion cell down to “empty”, around 2.5V or lower, removes most of the energy that could heat the cell in case it was physically damaged or short-circuited. The cell won’t be damaged internally by a discharge down to its rated cutoff voltage. Current will flow if the cell is short-circuited but its voltage will sag so far down that the current level is very low,
- Discharging certain cells (I don’t know which) down to under 2.0V or so can lead to some dissolution of the copper foil (that the negative battery goop is spread on) into the electrolyte. This in itself isn’t a safety issue as I understand it.
- A cell at zero volts has nothing in it that can do anything bad…unless you open the cell. There’s essentially no metallic lithium in the cell and no energy is left.
- But if overdischarged cells are then recharged that (possibly) dissolved copper will begin to plate onto different parts of the cells where it doesn’t belong. If the cell was discharged down far enough for long enough (or enough times, it’s all cumulative) then there could possibly be an internal short-circuit. It could be a very “soft” short-circuit, a few microamps to milliamps, that just slowly drains the cells. Or it could be a “hard” short-circuit that forces the cell into runaway. This isn’t what “dendrites” typically refer to though.
- Lithium metal dendrites typically form during overcharging (too high a voltage) and discharging/charging at too high a rate. They can start growing from either the positive or negative side of the cell, or both. This can, for some cells, also be a normal part of their aging with the dendrites slowly growing over time. If these lithium dendrites get long enough they can possibly poke through the insulating separator between the positive and negative parts of the cell and soft or hard short circuit the cell. As dendrites grow that also means less lithium that can be shuttled around as ions, causing a drop in cell capacity.
- This is all for single cells. Cells in series in a pack can bring up other issues, like the “reverse charging” that happens if a cell is forced to discharge below zero volts. This is incredibly dangerous.
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Nice !!!
My battery🔋 is done aswell.
@Simeon did a great job even on the little details.
The esc is definitely a tight fit its gonna be intresting fitting a cool plate.
Curious how you gonna setup the esc ( how many amps you will be running per motor)
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I took the design to my local machine shop to have it CNCd, excited to see how much I messed up 
Measure once cut thrice right?
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if it works, i might want a piece
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How much did you get quoted for that much milling?
I didn’t, I’ll find out when it’s done . Speaking of, since I know nothing about the process, which part of my design is most expensive/time consuming to make? The fins?
Probably the fins yep, they’d be annoying to cut. It’s either that or any tapping of holes, if that’s needed.
@SabreDynamics probably have a good idea of how difficult / easy something like this is, he makes custom cnc parts
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Oh boy… be prepared to shell out a couple hundred dollars lol
Be better if you’d make the fins a bit thicker, looks like they are 1mm now and that would probably mean they would have to be milled quite slowly to not cause any chatter while cutting, but there might be chatter regardless which leaves a bad finish. Id make them a bit thicker to be sure. Other than that it looks pretty doable. Because it needs two sides to be milled a fixture is needed so thats a bit of added cost, and you have a slight chamfer/3d surface on one edge which needs some extra attention while programming id reckon. Overall id probably quote this at around € 150, but I always check the cad model before I do a final quote.
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