Found an issue on the BMS board

I found that I had connected the cell sense pins in the wrong order. I had connected them like this: B- to VC0, B+ to VC1 and cell 1 to VC2, but it should have been connected like this: B- to VC0, cell 1 to VC1 and B+ to VC2. I almost didn’t notice it because I didn’t check that part of it. I thought that I wouldn’t have made a mistake like that. This wasn’t the only issue with the sense connections the other was that I didn’t use kelvin connections for them. Without kelvin connections you will get less accurate readings because of voltage drop in the copper.

I also improved it a little. I added cutouts for the current sensing resistor so I have separate pads for the sensing traces and the high current path. This should improve the current sensing accuracy which means I get a more accurate battery charge estimate. Then I added buttons for waking the IC up for programming and for shutting the output down so the battery can safely be removed. I moved the connector for the thermistors and the balance lead to the other side so the wires won’t have to run near a high current switching inductor which is on the main PCB.

Thank you for reading!