Do the eco go 56v battery packs have an BMS and if i use it for ebike swill it have to be removed can i??

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Chass Duff

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Posted 5 months ago

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summetj

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The batteries have a built in BMS.  I suspect you can draw power from the batteries without removing the BMS, as long as you don't go over the regular usage amp limit for that battery, but I haven't confirmed this.  (The 56 v is present on the terminals for a multimeter, so there doesn't appear to be any communication to the BMS needed to "enable" the battery....but I have actually tried to draw power from a battery using anything other than an EGO tool...)
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Official Response
You can use an Ego battery that way, but there will be no protection against overload, over temperature or over discharge. The warranty will also be void.
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Charles

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Does this mean that the built in BMS doesn't actually manage the battery voltage at all? It's all being done by the ego power tools and chargers?

I'm also interested in using the ego batteries in this way, as they are very well designed, and seem perfect for this purpose. 
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Blue Angel, Champion

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Overload, over temperature and over discharge are controlled in the tools.  This is necessary as there is a direct connection between the battery cells and the terminals, so the battery circuitry has no way of controlling or interrupting the current being drawn.  As far as I know most power tool battery/tool interfaces are designed this way.  I've seen projects where people use batteries from pretty much all major tool brands for power, but again, protecting the battery becomes the user's responsibility.

The BMS is inside the battery end cap.  From what I can tell, it talks to the charger through the "D" terminal (absent on the newer tools) and manages cell balancing as well as Ego's self discharge long term storage mode where the battery automatically discharges to 30% capacity if it sits unused for 30 days.
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Charles

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That makes a lot of sense. The different tools use different motors, and would need to be protected differently. Building the protection into the tool itself must make it easier for the batteries to be universal.

I’ll need to see if the standard ebike controllers are sufficient to protect the battery, or if another layer of protection is necessary.
(Edited)