As an energy storage solution, liquid Na/NaI-I2 cells are an option for rechargeable batteries at operating temperatures of 100℃. In these systems, molten sodium makes up for the anode, a NaSICON ceramic as separator, and the cathode is comprised of iodine-based solution. To realize these batteries, tight sealing and electrically insulating properties of the materials are needed. In this work, two glass compositions of B_2O_3-Al_2O_3-Na_2O-SiO_2 system are investigated as joining material for Ti (Grade 2) as battery body material and NaSICON as cell separator. Dilatometry measurements were conducted for sintered glass bars and elongation behaviour was compared to titanium housing and ceramic separator material. The viscosity behaviour of these glasses was examined by thermo-optical microscopy using TOMMIplus. Suitable sealing temperatures for both glasses were selected from differential scanning calorimetry and TOMMIplus measurements. Joining experiments were carried out with Ti (30 x 30 mm~2) metal plates, glasses and NaSICON (20 x 20 mm~2) separators, followed by He-leakage test of the joined samples. The interaction between ceramic/sealant/titanium was investigated by means of SEM/EDS. Both glass compositions demonstrated reliable sealing at joining temperatures in the range of 650-700℃.
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