The controller LVC is for the whole stack of batteries attached to it--it doesn't "talk" to any individual pack in there, so can't know anything other than total voltage.BatJ wrote:Amberwolf, the dewalt packs (at least the 18/20v ones) don’t have LVCs. The LVC in the controller wouldn’t sense the voltage of the lower pack would it? It’s not often I wouldn’t have the packs equally charged but it would be something that could go wrong.
Syonyk wrote:In the middle are some other terminals of interest. From left to right, top to bottom: TH, ID, C1, C2, C3, C4.
A tiny bit of experimentation with packs demonstrates that C1-C4 are actually the individual cell bank voltages, conveniently brought out for my use!
One thing of note here: The battery is always connected to the terminals. There is no way that the BMS can cut off current if the pack voltage is low. It's up to the tool to determine the cutoff point and refuse to work below that.
This also means that if you stick something in the terminals, you can get power out. Don't leave it running and drain the pack, but this would be a really easy pack to repurpose should you care to do so. There's literally nothing to do but jam metal blades into the B- and B+ terminals.
That’s what I suspected regarding the controllers LVC.amberwolf wrote:BatJ wrote:
spinningmagnets wrote:The DeWalt "Flexvolt" 60V packs are definitely 15S. They have a clever internal arrangement that is automatically configured as 5S / 3P, or 15S / 1P, depending on which tool they are plugged into. If you charge to 4.2V per cell, the top voltage when fully charged is 63.0V...
That being said, I really like the 14S / 56V EGO packs very much. I can verify that they are 14S. The individual cells are sleeved with a type of "phase change material" (PCM) where it can absorb a significant amount of heat from the cell during peak draws (it converts from a solid to a soft rubber), and then it sheds that heat over time. The packs spread the cells out just enough so air can be fan-circulated through the pack during charging and also discharge.
They definitely use high-amp cells to reduce the amount of heat that is generated in the first place. You can get them in 5.0-Ah and 7.5-Ah sizes. I have the mower and the weed-wacker, and I'm very pleased with both.
https://www.electricbike.com/cordless-t ... for-ebike/
Yup, that's why I was hoping to get by with one of these Greenworks 80v packs. But I need something that can handle 40Amp peaks and based on Spinningmagnets response, it sounds like I would wreck these things.999zip999 wrote:It's easier to have one pack of the same voltage and more than enough amperage hour that you need then multiple packs that must be all of the same voltage all the time. Last chance for trouble. 36v or above battery. Do you want a battery hobby or a ez running ebike.
Or you could the 18v nominal input into a DC boost converter while using a regular controller. I think mine will accept input voltages from 10V to 60V and output up to 90V. The boost converter I'm using also has a configurable LVC. I think most do. Some even make it easy to set via an integral digital display.amberwolf wrote: Alternately, you can use controllers that don't have an LVC; there's at least a few really cheap types out there for scooters and such. Some brushed, some brushless. But some of those also dont' have current limiting either, which might cause you some issues. I don't recall ATM which specific ones, but some of the places that sell cheap scooter stuff probably have them.