Oh boy that’s a long thread.
I’ll have to respond to all of the ideas here.
Agro first:
- 50mA minimum charging current. Ok then. However, 50mA-100mA-100mA+100nmA will have to do.
- 2 larger outer slots would work, but it would require a more custom design. Not more expensive. Just takes more time.
- Capacity measurements will start at 100mA, right up until 700mA. Rather than using resistors, we’ll maybe be using linear fed MOSFETs for discharge. 1A would be doable, but the fan would have to be very good, or use a 90mm internal fan/120mm external fan.
Higher is not possible.
- Good idea, but something I do not want. Good 4,20V terminal charging would be best.
- USD PD input would be very nice, but more expensive than a 5,5*2,5mm DC input jack.
@KevinZA1988, as I said with Agro, would be good. But would make the charger larger, and require a stand to work well. Costs are a bit limited here, so… maybe.
@Lux-Perpetua, storage mode is already included in the list.
Sudden off protection like on a PC can easily be done, and the charger wouldn’t come on until you press a button.
@Grigio, how about a color LCD display to the likes that RD Tech uses? That would be nice.
@delete, unfortunately, that would be too low with the kind of features we want.
A simple 18650/21700 8A charger could be doable without all the added features, but keep the most important ones, like a large current range and charging voltage selection.
@AEDe, thanks for the suggestion for Folomov. Will try to be careful with them if we decide to choose them.
About that non-standard battery charging. We could go include nickel plated neodymium magnet connectors to charge other devices.
@tempo, I’d rather say 49$US for a complete charger.
Powerbank functionality? Yes, but limited to a max of 900mA per the USB 3.0 spec.
USB-C PD input? No for cost reasons.
USB-A output/USB-C output for data? Yes of course.
USB-C input for updates? Yes.
WiFi or Bluetooth? Yeah no…
@varbos, increased the length to 80mm instead of 78mm.
@1332332331, microSD it is.
@hasddie293, this is what I’m implementing a full charge cutoff at 4,2V. Doesn’t charge back up until 4,0V.
For voltage cut off, something like a large capacitor would help.
No C-Rate functionality.
USB-A output at 5V 900mA, or maybe 5V 1,75A.
Good accuracy is important.
@WalkIntoTheLight, absolutely.