Hey Everyone
Out of pure curiosity, itchy fingers and an issue of unavailability of a travel charger I decide to slap together an 18650 battery charger.
Yeah it doesnt look too great at the moment, but it works like a charm.
Parts used:
TP4056 charging module
Single 18650 battery sled
0.28 Inch 3 Digit Volt Reader
Solid Core Copper Wire
Circuit as Follows:
As simple as that. Both Voltmeter and Charging module soldered directly to connector pins on the battery sled.
The TP4056 boards allow for a maximum of 1A charging which is perfect (allowed charging current of batteries are usually half its Ah rating as a rule of thumb - so the lowest batteries Ive got are Samsung 25Rs at 2600mAh, meaning they can handle 1.3A charging current), however should you wish to limit it, there is provision for a soldering on a resistor. With this exact build, the voltmeter displays 0.02V below the actual voltage, so the internal resistance of the voltmeter and wiring used is insignificant. The chip stops charging once the batteries reaches capacity (Tested voltage with my Multimeter and the batteries were at 4.19V without considering internal resistance of the multimeter itself) and has a built in LED that notifies you accordingly. The only flaw with this chip Ive found is that it uses the old school Mini-USB connectors, but cables arent hard to come by luckily.
These parts (excluding the sled) can be found locally at an array of electronics stores. I purchased everything from Fasttech though because it was dirt cheap. SKU's as follows:
TP4056 Charging Module: 1453504
Voltmeter: 3682006
Battery Sled: 3827606
Now, to make a housing and make pretty enough for transporting purposes.
PS, should you wish to make a dual/tri/quad bay charger, each cell will need its own TP4056 module and you can wire each chip in parallel at the input pins, although the current would then be divided by the amount of chips you are powering. Suggest you possibly investigate using a different module should you need a >1 Balancing charger (otherwise just buy a nitecore lol).
Out of pure curiosity, itchy fingers and an issue of unavailability of a travel charger I decide to slap together an 18650 battery charger.

Yeah it doesnt look too great at the moment, but it works like a charm.
Parts used:
TP4056 charging module
Single 18650 battery sled
0.28 Inch 3 Digit Volt Reader
Solid Core Copper Wire
Circuit as Follows:

As simple as that. Both Voltmeter and Charging module soldered directly to connector pins on the battery sled.
The TP4056 boards allow for a maximum of 1A charging which is perfect (allowed charging current of batteries are usually half its Ah rating as a rule of thumb - so the lowest batteries Ive got are Samsung 25Rs at 2600mAh, meaning they can handle 1.3A charging current), however should you wish to limit it, there is provision for a soldering on a resistor. With this exact build, the voltmeter displays 0.02V below the actual voltage, so the internal resistance of the voltmeter and wiring used is insignificant. The chip stops charging once the batteries reaches capacity (Tested voltage with my Multimeter and the batteries were at 4.19V without considering internal resistance of the multimeter itself) and has a built in LED that notifies you accordingly. The only flaw with this chip Ive found is that it uses the old school Mini-USB connectors, but cables arent hard to come by luckily.
These parts (excluding the sled) can be found locally at an array of electronics stores. I purchased everything from Fasttech though because it was dirt cheap. SKU's as follows:
TP4056 Charging Module: 1453504
Voltmeter: 3682006
Battery Sled: 3827606
Now, to make a housing and make pretty enough for transporting purposes.
PS, should you wish to make a dual/tri/quad bay charger, each cell will need its own TP4056 module and you can wire each chip in parallel at the input pins, although the current would then be divided by the amount of chips you are powering. Suggest you possibly investigate using a different module should you need a >1 Balancing charger (otherwise just buy a nitecore lol).