Pioneer study of SiP2 as negative electrode for Li- and Na-ion batteries

For the first time it is demonstrated that a dense SiP₂ pyrite-type obtained by a very simple ball milling method delivers outstanding capacity in both lithium and sodium batteries with up to 1000 mA h g⁻¹ and 572 mA h g⁻¹ sustained after 30 and 15 cycles respectively.