How to make Power Bank that simple and slim design? slim design power bank models can be easily made with parts easily found at this time. consists of custom plastic holder, a thin smartphone batteries, mini step up converter 5 Volt USB module, mini switch, and solid copper wire. custom battery holder base can be resized to fit the size of the rechargeable mobile Li-Ion battery.
Parts:
Step Up DC 0.9-5V To USB 5V 1200mA Charger Mobile Booster BB-10B
Rechargeable Mobile Li-Ion battery 2250mAh (larger is better)
solid copper cable wire
custom base battery holder
DPDT Miniature Slide Switch On-Off
Several smartphone have already tested with this simple Power Bank project, Test Result:
Test 1, Sony Ericsson Aspen (1500mAh), +/- 15 minutes charging, Result: 66% to 99%
Test 2, Lenovo Vibe K4 Note (3300mAh), +/- 15 minutes charging, Result: 22% to 31%
Test 3, Asus Zenfone 4 T001 (1600mAh), +/- 15 minutes charging, Result: 69% to 78%
for more clearly, please to see the video on Youtube, click on the image below:
Note: all smartphones in test is turned off before charging.
you can follow this tips, if you want to built this project:
if USB module produce much heat, it is needs additional heatsink.
Overheating a step up USB module has effect on the coil's lifetime.
usb module producing much heat during operation, need additional heatsink for save module.
because this is simple design, it has shortcomings rather than ordinary Power Bank.
for further design, it need to upgrade on converter board, using power bank board module can resolve this.
more features available if use power bank board module than regular step-up converter 5 volt module, but the design may not slim anymore. using battery 3000 mAh or more is recommended.