<p>The wide application of LiFePO₄/C cathode material is often circumvented by low electrical conductivity and sluggish Li⁺ diffusion rate. Herein, Na⁺ and Ti⁴⁺ doping was adopted to alleviate above problems. The formation energy, Li–O band length, and electronic structure were analyzed by first principle calculations to study the effect of Na⁺ and Ti⁴⁺ doping on LiFePO₄ material. The calculations show that Ti⁴⁺ ions are inclined to occupy Fe site, Li–O bond is lengthened, and the band gap is decreased after doping. On this basis, undoped, Ti⁴⁺-doped, and Na⁺/Ti⁴⁺ co-doped LiFePO₄ samples were prepared by wet ball milling, spray drying, and carbothermal reduction method. It is found that Na⁺ and Ti⁴⁺ doping obviously enhances Li⁺ ion diffusion rate and electrical conductivity of material, thereby improving the electrochemical performance of material. The increase of Li⁺ ion diffusion rate can be mainly attributed to widened Li⁺ diffusion channel, lengthened Li–O bond, and shortened Li⁺ diffusion path after Na⁺ and Ti⁴⁺ doping. The electrical conductivity is also increased to 10⁻¹ order of magnitude after Na⁺ and Ti⁴⁺ doping, in consistence with the lowered band gap. Among them, Li_0.98Na_0.02Fe_0.99Ti_0.01PO₄/C material displays the best electrochemical performance in coin-type cell and 14,500 cylindrical battery.</p>