was made but this was a poor workaround,
and was primarily intended for another camera. It does not solve camera feeding during very long
timelapses or when attached to instrumentation.
The Canon Powershot A2600 camera has no in-camera charger. The external charger is operated from mains power, and the proprietary module is bigger than the camera itself (especially when the power cord is also counted), is a hassle to carry around and is liable to be lost.
A smaller, USB powered charger was made but this was a poor workaround,
and was primarily intended for another camera. It does not solve camera feeding during very long
timelapses or when attached to instrumentation.
The camera also has no way to attach an external power supply. There is a proprietary adapter that plugs in instead of the battery, but it is extra expensive and not easy to find.
Something had to be done.
The camera was disassembled and inspected. The battery terminals
were located on the circuitboard. A pair of thin wires was attached, red for positive and black
for negative line, to the + and - terminals of the battery. Fairly thin wires had to be used to
get them through the cramped internal space of the camera with ease.
The wires were pulled through a hole in the camera case. A small TP4056-based charger board was attached to them; its miniUSB connector was replaced with a microUSB one (for which the board already had pads on the circuit; the connector was also soldered along its entire bottom instead of just the side pads, because it will be subjected to major forces).
The same module as for the TicTac charger was used here.
For now, the charger board was wrapped in painter tape for insulation and attached to the exterior of the camera using a piece of double-sided foam tape.
 Wire attachment |  Wire attachment |  Wires out of the assembly |  Charger on the outside |
 Charger on the outside |  Charger on the outside |  Charger on the outside |  Charger on the outside |
The chip is providing constant current/constant voltage charging, with 0.1 current cutoff. The current limit is set with a little 0603-sized resistor on the board, between a chip pin and ground; a tenth of this current ends charging. The chip provides limited current to the moment the battery voltage reaches the limit (4.2 volt), then limits the voltage and the current gradually tapers off; when it reaches 10% of the set value, the charging is ended, the red light is switched off, and the green light is lit.
The chip's logic is friendly with feeding circuitry attached to the battery. When the battery gets loaded, its voltage drops a little, this signals the chip to start charging. The provided current is partially sunk by the battery to replenish itself, partially by the attached circuitry. When the circuitry takes more current than the chip can source, the battery will provide the rest.
With an external power supply, and when the battery is fully charged, switching on the camera turns the light red, switching it off turns the light green in short time again.
Build an extra-small version of the module, embed it into the camera chassis itself. There should be enough space for a chip and a pair of LEDs.