Hi, Team Hologram and Everyone,
I’m looking for a recommendation for a cylindrical cell to use as a backup battery. The Hologram-supplied PK Cell pouch cell works great, but I’d ultimately prefer a cylindrical cell due to it’s sturdy package (vs. a pouch cell).
I’ve now tested a few PCB-protected 10440 and 18650 cells, but I’ve come up against an interesting issue: When used as a backup cell, the cells perform fine and shut off at the claimed lower-limit voltage. Unfortunately, they “latch” there, so that returning 5V USB power does not allow charging resumption / Dash function without first disconnecting and then reconnecting the battery to the circuit. That means that auto-reboot when USB power is restored is not possible. Conversely, the PK Cell does not exhibit this behavior: When it shuts off at low voltage, subsequent resumption of USB power brings the board and charging back online.
I recall that back in the “Dazzling Duke” days, there was talk of a Konekt making a protected 18650 cell available.
Possible commercial application being considered here, so I’d like to move to cylindrical from the easily-mishandled pouches. Any recommendations are much appreciated!