abandoned Solar cells It could have a second life in the future. Batteries Received. Chinese researchers have recycled that. Silicon In it to put it on Anode to use.
Currently this is mostly done Graphite User. Research into silicon anodes has been going on for some time because they… higher energy density Those with graphite can achieve this. However, the big challenge is that the silicon first swells significantly during charging and then loses volume again. Thus the anode becomes after only a few charging cycles crisp And commas.
➤ Read more: How to Give Used Solar Panels a Second Life
The protective layer holds the silicone molecules together.
The researchers used micrometer-sized silicon particles for the anode. To keep it stable, a special one comes By electricity For use. Its formula of lithium hexafluorophosphate, 1,3-dioxane and the solvent 1,2-diethoxyethane ensures the formation of a kind of protective film around the silicone.
Above the fragile SEI, below the new double-layer SEI.
© Liu Tao
this Solid electrolyte interphase (SEI) They are usually brittle, but the electrolyte makes them brittle. Double layerIt remains flexible but strong enough to hold the silicone molecules together if it breaks.
high energy density
In addition, the ionic conductivity should be improved and side reactions should be reduced. This is how they survived. 80 charge cycles Under harsh laboratory conditions. The energy density of 340.7 watts per kilogramFor comparison: a Tesla battery has an energy density of 240 to 300 Wh/kg.
Capacity is still over 80 percent after 200 charging cycles.
In tests, this ensured a high level of electrochemical stability. The so-called “Coulomb efficiency“”According to scholars 99.94 percentThis means how much capacity the battery still has after a complete charge and discharge cycle.
after 200 charge cycles The battery still has 83.13 percent Capacity. Typical charging cycles for lithium-ion batteries range from 500 to 800 charging cycles, while for electric vehicles it often reaches 1,000 cycles. This depends on the remaining capacity, which is often less than 70 percent.
Sustainable recycling of valuable materials
“Sourcing silicon sustainably from discarded solar modules reduces both,” economic as well as that environmental “The impact of photovoltaic waste,” says Dong Tiantian, one of the study’s authors. In the current situation.
Converting waste into valuable battery components would also help. it costs For lithium ion batteries and accessories Availability Yazid. Study results Published in Nature Sustainability.
