Page 6 - Guide to Lithium-ion Battery Solutions
P. 6

Material Testing





                  Compression test of various materials that construct a Lithium-ion Battery                                                   Purpose                                        Samples


                                                                                                                                        Compression test of solid electrolyte raw       Two types of solid electrolyte raw materials
                                                                                                                                        materials
                                                       Micro Compression Tester

                                                       MCT Series
                                                                                                                                               Data
                                                       •   Consideration  of  conditions  for battery packaging and
                                                         restraint pressure
                                                       •   Examination of manufacturing process conditions (change in
                                                         strength during heating)



                  Inner structural materials of a Lithium-ion Battery are subjected to external force during production processes and to
                  pressure during use. Therefore, evaluating the strength of each structural material is important to maintain consistent
                  quality. Below are the results of compression tests performed on Lithium-ion Battery materials using the Micro
                  Compression Testing Machine.



                                                                                                                                                            Before                                          After
                         Purpose                                        Samples

                  Compression test of positive electrode active   Two types of positive electrode active                                Compression Test Results
                  materials                                      materials
                                                                                                                                            Sample   Fracture strength  Particle size  Strength
                                                                                                                                            Name        [mN]       [µm]      [MPa]
                         Data
                                                                                                                                              A         1.25       1.765      315
                                                                                                                                                                                           Force (mN)
                  Compression Test Results                                                                                                    B         0.63       4.265      27

                     Sample   Fracture strength  Particle size  Strength
                      Name        [mN]       [µm]      [MPa]
                                                                         Force (mN)
                                  1.67       13.0      7.79
                     LiMn 2 O 4                                                                                                                                                                            Displacement (μm)
                                 16.23       13.3      72.75
                     LiCoO 2
                                                                                                                                                                                                    Test force-displacement graph
                                                                                                                                               Result
                                                                                 Displacement (μm)
                                                                                                                                        By measuring the fracture strength, we can compare the correlation with the ease of molding as an electrolyte.
                                                                              Test force-displacement graph
                                                                                                                                        Comparing particles A and B shows that the fracture strength of particle B is about 1/10 weaker. This indicates that the
                                                                                                                                        particles adhere well to each other during the molding process.
                         Result


                  The force is on the vertical axis, the displacement is on the horizontal axis, and fracture occurs at the inflection point
                  where the displacement becomes horizontal. The fracture strength of the lithium cobalt oxide LiCoO 2  particle was
                  measured to be 72.75 MPa compared to 7.79 MPa for the lithium manganese oxide, LiMn 2 O 4 .




                                        Click here for product page                                                                                            Click here for product page




        6                                                                                                                                                                                                                                    7
                                                                                                            index                                                                                                                  index
   1   2   3   4   5   6   7   8   9   10   11