Structure information of electrode materials obtained by neutron power diffraction is very expedient to understand the conduction mechanism of second battery. Data about a local structure change such as a position and occupation of conduction ion give us a clue for realizing the next generation second battery with high-capacity, high-efficiency and good-safety. To analyze neutron powder diffraction data, combining with Rietveld refinement and Maximum Entropy Method (MEM) is very useful to fully understand a local structure change of electrode. A local-structural change in electrode materials is observed when the electrode materials have been experienced the charging/discharging, doping, particle size control and spin ordering process etc. It is possible to design a beyond battery material with high performance by controlling a local-structure as functions of several external conditions.  In this talk, we will introduce the crystal and magnetic structure studies of battery materials using high resolution neuron powder diffraction (HRPD) in HANARO. For examples, we have investigated the magnetic and crystal structure of Na_xFe₃(PO₄)₂(P₂O₇) (1 ≤ x ≤ 4) with a mixed polyanion framework using neutron powder diffraction. The new compounds contained three-dimensional (3D)-sodium paths supported by P₂O₇ pillars in the crystal. The de/sodiation of the Na_xFe₃(PO₄)₂(P₂O₇) electrode occurs via a one-phase reaction with a reversible Fe²⁺/Fe³⁺ redox reaction and accompanies an exceptionally small volumetric change of less than 4%.  Very interestingly, we have observed a very strong spin-lattice coupling behavior in this compound. Even though, the spin ordering of this material is happened at a low temperature, the trials to understand a strong correlation between spin and lattice within electrode materials are valuable to open an opportunity which realizes the new concept’s second battery to be controlled the conduction property of electrode by the spin ordering.