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ABSTRAK Samuel Rahardian
PUBLIC Alice Diniarti

COVER Samuel Rahardian
PUBLIC Alice Diniarti

BAB 1 Samuel Rahardian
PUBLIC Alice Diniarti

BAB 2 Samuel Rahardian
PUBLIC Alice Diniarti

BAB 3 Samuel Rahardian
PUBLIC Alice Diniarti

BAB 4 Samuel Rahardian
PUBLIC Alice Diniarti

BAB 5 Samuel Rahardian
PUBLIC Alice Diniarti

PUSTAKA Samuel Rahardian
PUBLIC Alice Diniarti

Lithium-ion battery has been used as the power source for electrical device such as drone, sensor, electric car, etc. Pouch battery was one of the most preferred battery configurations due to its compactness and high energy density. This thesis investigates battery configuration to its structural integrity under bending loads as the most critical damage type which can occur when a crash happens. Short circuit due to separator failure causing the anode and cathode active material connected could lead to fire/explosion. A three-point bending test was conducted for different pouch battery configurations to obtain force-displacement curves. The finite element model of the pouch battery under the three-point bending was then simulated. A homogenization technique was applied in the model to significantly reduce the simulation cost and time consumption. The Force-displacement curve from the simulation result was then extracted and compared with the curve obtained from the bending test. Furthermore, the stress distribution and deformation inside the pouch battery under bending loads were then investigated. A region in which a short circuit might occur was then identified from the Representative Volume Element (RVE) model. The role of folded configuration and its battery casing to resist flexural damage was then confirmed by structural strength improvement of 14 and 30 times, respectively. The casing and folded configuration could protect the battery failure because those could effectively bear almost all shear stress during the bending load, which always became the main cause of damage in the battery structure. From the three-point bending testing, the usage of liquid electrolyte had high risk of fire which leads to unsafe condition during the battery operation. The countermeasure against the fire potential to increase the safety aspect and reliability of the lithium-ion battery need to be improved. To tackle fire/explosion that may happen when using liquid electrolyte, solid electrolyte is introduced. This battery type is called Solid State Battery (SSB). By using SSB, solid electrolyte could prevent the fire/explosion due to its ability to prevent the contact between anode and cathode and prevent dendrite formation significantly better than liquid electrolyte-based lithium-ion battery separator. Furthermore, SSB could provide higher energy density than liquid electrolyte-based lithium-ion battery due to its ability to use anode with higher energy density such as Indium. However, during battery cycle, the electrodes expand and shrink due to Lithium-ion diffusion. The usage of solid electrolyte imposes new problem that could damage the solid electrolyte, thus reducing its electrical performance. This thesis reveals mechanisms of crack formation in solid electrolytes due to compressive loading generated by electrode expansion. Three scenarios of anode-electrolyte-cathode arrangements were examined numerically with different expansion-shrinkage behavior. The crack formation inside the electrode was represented by inserting a cohesive element between the mesh of the model. Stress in electrolytes caused by electrode volume change was then investigated. The crack formations from the numerical simulation result were then used for simulating electrical behavior to examine the internal resistance change. The result shows that high volume expansion change increases the crack generation inside the electrolyte. From the simulation, it was shown by using low strain rate electrodes, crack inside SSB electrolyte could be reduced and provide better battery performance with lower degradation rate. The research for low strain material needs to be conducted to increase the performance of SSB.