1 EBaM: an EDA tool for Battery Modeling POLITO www.arrowhead.eu
Outline …Energy efficiency is often centered around the “device” …But overall efficiency can be decided in other parts of the “energy path” MPP M T PP DC- C DC Energy DC-DC I, V & co c n o v n e v r e te t r e / DC-DC source converter co c nt n ro r l o cha h r a g r e g r e converte t Energy storage load (Optional) device (ESD)
3 Automation for battery modeling Many battery models, with different complexities, are proposed in L li itm eritaatt u iroen . s: Costs & Time: calculation of model parameters is based on actual measurements Lack of generality: a given circuit/model cannot be used to represent another device, i.e., validation is carried out on the specific battery under measure Solution: Modeling from datasheet: resort to information available in the datasheets provided by the battery manufacturers; Variable accuracy model templates: since datasheets often provide limited info, adapt the model template (accuracy) to the amount of information.
Battery Models should include... I-order effects: II-order effects: Temperature Battery runtime; effects on battery voltage; Temperature SOC-OCV relation; effects on capacity; SOC-transient Capacity fading response relation. due to cycling and storage (aging).
Model levels overview
Level 1 Level 2 Level 3 RunTime RunTime RunTime I SOC SOC SOC Orde Steady-State Steady-State r Response Response Effec Transient ts HIG Response H A E C R Level 1 Level 2 CU Level 3 R II A
+ Temperature + Temperature CY + Temperature Orde r Level 1 Level 2 Level 3 Effec + Capacity + Capacity + Capacity ts Fading Fading Fading
Level 1 model
battery runtime; temperature effects; possibility to further extend it for capacity fade.
Level 2 model Equivalent electric circuit model battery runtime; SOC-OCV relation; temperature effects; possibility to extend it for capacity fade.
Level 3 model battery runtime; SOC-OCV relation (transient); temperature effects; possibility to extend it for capacity fade.
Accuracy Level 2 Sony UP383562 constant current @0.0008C Level 3 2s @0.1C Energizer CR2032