An Insight into the Battery Degradation for a Proposal of a Battery Friendly Charging Technique

Abstract Li-ion batteries are widely used in electric vehicles because of their promising characteristics that meet high specific power and energy density requirements. The only setback is the capacity fading due to degradation in Li-ion batteries. The rate of capacity fade in Li-ion batteries in EVs vary based on the charging rate, changes in internal cell temperature and external ambient temperature, and user driving patterns. Since the Li-ion battery is electrochemical, determining the actual cause of degradation at a particular instant and constraining the rate is a big challenge. Further, the causes are related to parameters which are chemical, electrical and mechanical. In this work, the causes of degradation are studied by analysing the variation of parameters for multiple charge types and rates at different ambient temperatures. The analysis leads to developing a new universal charging scheme suitable to fast charge battery at different ambient temperatures appropriately and constrain battery degradation.</jats:p

An Insight into the Battery Degradation and a Proposal for a Battery Friendly Charging Technique

Abstract Li-ion batteries are widely used in electric vehicles because of their promising characteristics that meet high specific power and energy density requirements. The only setback is the capacity fading due to degradation in Li-ion batteries. The rate of capacity fade in Li-ion batteries in EVs vary based on the charging rate, changes in internal cell temperature and external ambient temperature, and user driving patterns. Since the Li-ion battery is electrochemical, determining the actual cause of degradation at a particular instant and constraining the rate is a big challenge. Further, the causes are related to parameters which are chemical, electrical and mechanical. In this work, the causes of degradation are studied by analysing the variation of parameters for multiple charge types and rates at different ambient temperatures. The analysis leads to developing a new battery friendly charging scheme suitable to fast charge battery at different ambient temperatures appropriately and constrain battery degradation.</jats:p

Formulation of Stray Loss in Medium Power Inverter-fed Induction Motors

&lt;div&gt;The work presents a fast and accurate empirical stray loss model for inverter fed three-phase induction motors (IMs). The model is intended to quantify the SL both at the design stage and, normal operation of the IM. The development of the model considers the variations of frequency, switching frequency and motor’s loading. Test data of 128 operating points of two training IMs are used to develop the model. The accuracy and prediction capability of the proposed model is presented with the measured SL values for 128 operating points of another set of two IMs of the same specifications and different geometries.&lt;/div&gt;</jats:p

Formulation of Stray Loss in Medium Power Inverter-fed Induction Motors

&lt;div&gt;The work presents a fast and accurate empirical stray loss model for inverter fed three-phase induction motors (IMs). The model is intended to quantify the SL both at the design stage and, normal operation of the IM. The development of the model considers the variations of frequency, switching frequency and motor’s loading. Test data of 128 operating points of two training IMs are used to develop the model. The accuracy and prediction capability of the proposed model is presented with the measured SL values for 128 operating points of another set of two IMs of the same specifications and different geometries.&lt;/div&gt;</jats:p