Batteries are currently a technology holy grail, with teams around the world trying to find new energy-storage solutions that would allow renewable electricity to be used without fossil-fuel backup and smartphones and electric cars to last days on end without recharging.
While newer battery technologies can offer higher density than commonplace lithium-ion batteries, their capacity tends to drop rapidly after the first few charges.
The Uppsala researchers say their battery can be charged and discharged over 500 times without any significant loss.
They have demonstrated that their battery can be easily charged using a solar cell and that charging can be accomplished without the aid of the advanced electronics that lithium batteries require. It is also unaffected by ambient temperature.
"I'm sure that many people are aware that the performance of standard batteries declines at low temperatures. We have demonstrated that this organic proton battery retains properties such as capacity down to as low as -24°C," said Christian Strietzel of Uppsala University's Department of Materials Science and Engineering.
A great many of the batteries manufactured today have a major environmental impact, not least due to the mining of the metals used in them. Stores of key elements like lithium and cobalt are also expected to become critical by 2050 according to analysis from 2018.
"The point of departure for our research has therefore been to develop a battery built from elements commonly found in nature and that can be used to create organic battery materials," said Strietzel.
The researchers chose quinones as the active material in their battery. These organic carbon compounds are plentiful in nature, as they occur during the photosynthesis process among other things.
They utilised their ability to absorb or emit hydrogen ions, which contain protons, during charging and discharging.
An acidic aqueous solution has been used as an electrolyte. As well as being environmentally friendly, it reduces the risk of explosion or fire.
"There remains a great deal of further development to be done on the battery before it becomes a household item; however, the proton battery we have developed is a large stride towards being able to manufacture sustainable organic batteries in future," Strietzel said.