Due to the advantages of lithium-ion batteries, the distribution of this battery type has increased in the electric and hybrid vehicle industry. Frequently used materials in lithium-ion batteries are lithium mixed oxides, such as lithium cobalt nickel manganese oxide, lithium mixed systems, lithium manganese oxides or lithium iron phosphate. After the service life of the batteries all above-mentioned materials will be accumulated as waste. The high cost of some of the primary materials, such as lithium, nickel or cobalt, have augmented the importance of developing new recycling and treatment processes, in order to ensure the recovery of these valuable substances from the battery waste. However, the requirements for economic and ecologic recycling are reliable analytical methods that allow the exact characterisation of the used materials in the battery. Therefore, this master thesis focuses on finding an adequate analysis method for obtaining a comprehensive characterisation of the cathode material “lithium iron phosphate” applying FAAS (flame atomic absorption spectrometry), ICP-MS (Inductively Coupled Plasma Mass Spectrometry) and suitable digestion methods. As for the method development no reference materials could be purchased, a cathode with known stoichiometric composition and pure materials similar to the lithium iron phosphate were used for analysis. The cathode material and the pure substances were exposed to various acids and acid mixtures and afterwards examined by FAAS and ICP-MS regarding their element contents. For the determination of the main components recovery rates over 85 % were achieved for certain digestion reagents. Furthermore, the extended standard uncertainty for the used procedures was assessed.