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An approach for a fast recycling process for Lithium Nickel Cobalt Aluminum Oxide (NCA) cathode scrap material without the presence of a reducing agent was proposed. The combination of metal leaching using strong acids (HCl, H2SO4, HNO3) and mixed metal hydroxide co-precipitation followed by heat treatment was investigated to resynthesize NCA. The most efficient leaching with a high solid loading rate (100 g/L) was obtained using HCl, resulting in Ni, Co, and Al leaching efficiencies of 99.8%, 95.6%, and 99.5%, respectively. The recycled NCA (RNCA) was successfully synthesized and in good agreement with JCPDS Card #87-1562. The highly crystalline RNCA presents the highest specific discharge capacity of a full cell (RNCA vs. Graphite) of 124.2 mAh/g with capacity retention of 96% after 40 cycles. This result is comparable with commercial NCA. Overall, this approach is faster than that in the previous study, resulting in more efficient and facile treatment of the recycling process for NCA waste and providing 35 times faster processing.

Electrochemical synthesis of hydroxyapatite particles was performed from a homogeneous solution of Na2H2EDTA.2H2O, KH2PO4 and CaCl2 without stirring to investigate the mechanism of hydroxyapatite formation. We found that OHions generated by water reduction at the cathode play an important role in the formation of hydroxyapatite particles. The OHions induce the liberation of Ca 2+ ions and the dissociation of phosphoric acid, which serve as the reactants for the formation of hydroxyapatite particles. Two layers with a clear boundary were formed during electrolysis. The upper layer comprises the produced particles and the lower layer is a homogeneous solution. The produced particles were held in the region between the electrodes mainly due to the electrostatic interactions of charged particles in an electric field. The hydroxyapatite particles are agglomerates consisting of spherical particles. Aging the suspension for 24 h after electrolysis leads to the transformation of hydroxyapatite to brushite. Thus, if producing hydroxyapatite is desired, the particles should be continuously removed from the system. This method appears to be promising as a continuous process to produce hydroxyapatite particles using an electrochemical method.

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With the increasing development of the battery and electric vehicle industry, student's and teacher's understanding of lithium batteries and skills in assembling electric bikes are very important in competing for jobs in these fields. Educational activities regarding batteries and training on assembling electric bike are carried out at SMK Muhammadiyah 6 Karanganyar, because there were no facilities that support the learning and teaching process about electric vehicles and batteries. The method used in this training is lecture, discussion and practice method. The material presented was about the technology of making lithium batteries and electric bike components. While practical activities include the stages of converting conventional bikes into electric bikes with energy from lithium batteries. This activity shows that participants can understand batteries and can apply batteries to electric vehicles, especially electric bikes.

One of the most well-known material for lithium battery cathode synthesis of lithium ferro-phosphate type is iron phosphate precursor. The precursor is synthesized by the use of leaching method with tartaric acid solution with optimization at various leaching temperature and time. The temperature variables are at 30 ℃, 50 ℃, 70 ℃, and 90 ^oC. The time variables are at 3 hours, 6 hours, and 9 hours. The main material that is used is iron from used nickel plated A3 steel battery shell. The recovered iron concentration and quantity is calculated from absorbance by atomic absorption spectrophotometry (AAS). AAS analysis indicates the absorbed Fe is rated at 1,02 % (30 ℃, 2,76 % (50 ℃), 9,93 % (70 ℃), and 34,31 % (90 ℃) during 9 hours of leaching.The analysis indicates the recovered iron is rated the highest during 9 hours of leaching at the highest temperature. X-ray diffraction analysis at various leaching temperature variable indicates formation of iron phosphate crystal to be compared with iron phosphate commercial precursor, while scanning electron microscope analysis shows uniform iron phosphate particle morphology.