Solar Capacitor
Alternative to alkaline and rechargeable lithium-ion batteries.
A lightweight and safe energy storage device that gets recharged from the sun and suffers virtually zero performance loss over decades of service.
Problems with Li-ion batteries
- limited lifetime due to degradation of cathodes
- requirement for a sophisticated built-in charge controller
- wearing out and loss of efficiency after only a couple hundred cycles
- fire hazard due to their electrochemical nature
- significant efficiency drop in cold environments
Advantages of super capacitors over Li-ion batteries
- fire safety
- higher amperage output
- very simple, 100% analog design
- ability to sustain up to one million cycles
- resistance to both extremely cold and hot environments
- very fast charge time
- almost no heat generated during charge
Benefits of using solar capacitors
Having a solar panel built into the energy storage device provides conventience of being able to charge your “batteries” by simply taking them out of your device and leaving in a sunny spot.
Solar capacitors can also allow powering of small devices directly from the sun. Existing electronic devices can be easily modified to feature a transparent battery cover.
How it can be obtained
At the moment, solar capacitor’s design is available to everyone as a working prototype.
The design is open-source and has been released into the public domain.
Files can be downloaded at the bottom of this page.
9V
This design can feature either one or two solar panels, and has capacity of roughly 350mAh (2/3–1/4 of a conventional 9V battery).
Parts
- 2 × super capacitor
- 5 × solar panel
- 1 × terminals from a dead 9V battery
- 1 × diode
- 1 × 3D-printed body
The total cost of parts is around $40 USD.