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Simy · 07-07-2011, 08:45 AM

Don't worry about the lecture I'm always willing to learn and admit I know next to nothing when it comes to eletronics. Now, when I got my extra ham license I may have been able to make heads or tails of it but I didn't study batteries/chargers/BMS/motors so

Please forgive me if this is stupid but what limits this circuit to a 2.2-4.0V range? Also how accurate is the voltage measurement? Is it possible with a change to have a wider range without impacting the rest of the design? It looks like the PIC gets its power straight from the battery, assuming I'm correct on that then shouldn't its operating range vary from 1.8-3.6V? Or am I looking at the wrong chip?

Do you have a BOM so I can look at each part? Is it a 2 wire system where they all communicate on the same 2 wires, or is it 2 wires per battery/device?

I like the battery module but as for your master brain I may go my own route =) I would prefer my master module also accept the throttle input and give a throttle signal to the speed controller, and handle the charger as well.

I looked up how batteries charge and assuming you have a power supply capable of putting the correct power/voltage for your pack (or cells) then it should be fine. I'm not quite sure how the shunt works though, could you explain that to me?

I'm sorry if I seem like such an idiot, I'm sort of getting the hang of it but I've never really looked at making a circuit nor have I even though of using a PIC but seeing what it is capable of after reading a bit about it (just now...) I'm going to order the PICKIT 3 ASAP and a project to start playing with would be helpful. =) I learn best by doing anyways, even if it will take me awhile to "get it" I will. If I hadn't found this forum I would have been using a computer to do the same thing. $100+ as well as MUCH more power usage! PIC's are AWESOME!!!

Edit Below:
After rereading your post I just have to ask is the shunt the resistor to ground? Simply a way to waste energy? So in theory we could discharge ALL cells until Vmin, or we could continue to charge all cells (even past their max capacity) without damaging them because we are wasting power after we get to Vmax? Did how this balances finally "click".... correctly?

07-07-2011, 08:45 AM	#6 (permalink)
Simy EcoModding Lurker Join Date: Jul 2011 Location: Tampa, Florida, United States Posts: 28 Thanks: 5 Thanked 2 Times in 2 Posts	Don't worry about the lecture I'm always willing to learn and admit I know next to nothing when it comes to eletronics. Now, when I got my extra ham license I may have been able to make heads or tails of it but I didn't study batteries/chargers/BMS/motors so Please forgive me if this is stupid but what limits this circuit to a 2.2-4.0V range? Also how accurate is the voltage measurement? Is it possible with a change to have a wider range without impacting the rest of the design? It looks like the PIC gets its power straight from the battery, assuming I'm correct on that then shouldn't its operating range vary from 1.8-3.6V? Or am I looking at the wrong chip? Do you have a BOM so I can look at each part? Is it a 2 wire system where they all communicate on the same 2 wires, or is it 2 wires per battery/device? I like the battery module but as for your master brain I may go my own route =) I would prefer my master module also accept the throttle input and give a throttle signal to the speed controller, and handle the charger as well. I looked up how batteries charge and assuming you have a power supply capable of putting the correct power/voltage for your pack (or cells) then it should be fine. I'm not quite sure how the shunt works though, could you explain that to me? I'm sorry if I seem like such an idiot, I'm sort of getting the hang of it but I've never really looked at making a circuit nor have I even though of using a PIC but seeing what it is capable of after reading a bit about it (just now...) I'm going to order the PICKIT 3 ASAP and a project to start playing with would be helpful. =) I learn best by doing anyways, even if it will take me awhile to "get it" I will. If I hadn't found this forum I would have been using a computer to do the same thing. $100+ as well as MUCH more power usage! PIC's are AWESOME!!! Edit Below: After rereading your post I just have to ask is the shunt the resistor to ground? Simply a way to waste energy? So in theory we could discharge ALL cells until Vmin, or we could continue to charge all cells (even past their max capacity) without damaging them because we are wasting power after we get to Vmax? Did how this balances finally "click".... correctly? Last edited by Simy; 07-07-2011 at 08:48 AM.. Reason: Addition.