1. www.arrowhead.eu EBaM: an EDA tool for Battery Modeling 1 POLITO

2. 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” DC-DC converter/ charger MPPT & control MPPT & control load Energy source I, V t DC-DC converter Energy storage device (ESD) (Optional)

3. www.arrowhead.eu 3 Limitations:  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. Automation for battery modeling Many battery models, with different complexities, are proposed in literature.

4. www.arrowhead.eu EBaM Framework

5. www.arrowhead.eu Battery Models should include...

6. www.arrowhead.eu Model levels overview Level 1Level 2Level 3 I Order Effects RunTime SOC RunTime SOC Steady-State Response RunTime SOC Steady-State Response Transient Response II Order Effects Level 1 + Temperature Level 2 + Temperature Level 3 + Temperature Level 1 + Capacity Fading Level 2 + Capacity Fading Level 3 + Capacity Fading HIGHER ACCURACY

7. www.arrowhead.eu Level 1 model  battery runtime;  temperature effects;  possibility to further extend it for capacity fade.

8. www.arrowhead.eu Level 2 model Equivalent electric circuit model  battery runtime;  SOC-OCV relation;  temperature effects;  possibility to extend it for capacity fade.

9. www.arrowhead.eu Level 3 model  battery runtime;  SOC-OCV relation (transient);  temperature effects;  possibility to extend it for capacity fade.

10. www.arrowhead.eu Accuracy Level 2 Level 3 Sony UP383562 Energizer CR2032 constant current @0.0008C 2s @0.1C