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The thermoelectric performance of n-type Bi2Te3needs further enhancement to match that of its p-type Bi2Te3counterpart and should be considered for competitive applications. Combining Cu/Cl and multiscale additives (AgBiSe2) presents a suitable route for such enhancement. This is evidence of the enhanced thermoelectric performance of Bi1.995Cu0.005Te2.69Se0.33Cl0.03. Moreover, by incorporating 0.65 wt % AgBiSe2(ABS) into Bi1.995Cu0.005Te2.69Se0.33Cl0.03, we further reduce its lattice thermal conductivity to ∼0.28 W m–1K–1at 353 K owing to the extra phonon scattering of multiscale ABS. Additionally, the Seebeck coefficient enhances (−183.89 μV K–1at 353 K) owing to the matrix’s reduced carrier concentration caused by ABS. As a result, we achieve a high ZTof ∼1.25 (at 353 K) and a high ZTaveof ∼1.12 at 300–433 K for Bi1.995Cu0.005Te2.69Se0.33Cl0.03+ 0.65 wt % ABS. This work provides a promising strategy for enhancing the thermoelectric performance of n-type Bi2Te3through Cu/Cl doping and ABS incorporation.

Application of LiFePO4(LFP) to large current power supplies is greatly hindered by its poor electrical conductivity (10–9S cm–1) and sluggish Li+transport. Carbon coating is considered to be necessary for improving its interparticle electronic conductivity and thus electrochemical performance. Here, we proposed a novel, green, low cost and controllable CVD approach using solid glucose as carbon source which can be extended to most cathode and anode materials in need of carbon coating. Hydrothermally synthesized LFP nanorods with optimized thickness of carbon coated by this recipe are shown to have superb high-rate performance, high energy, and power densities, as well as long high-rate cycle lifetime. For 200 C (18s) charge and discharge, the discharge capacity and voltage are 89.69 mAh g–1and 3.030 V, respectively, and the energy and power densities are 271.80 Wh kg–1and 54.36 kW kg–1, respectively. The capacity retention of 93.0%, and the energy and power density retention of 93.6% after 500 cycles at 100 C were achieved. Compared to the conventional carbon coating through direct mixing with glucose (or other organic substances) followed by annealing (DMGA), the carbon phase coated using this CVD recipe is of higher quality and better uniformity. Undoubtedly, this approach enhances significantly the electrochemical performance of high power LFP and thus broadens greatly the prospect of its applications to large current power supplies such as electric and hybrid electric vehicles.