Electrochemical State-Based Sinusoidal Ripple Current Charging Control

Battery Impedance Analysis Considering DC Component in Sinusoidal Ripple-Current Charging

“…Thus, low frequency is preferred for the pulsed-current frequency in many studies (0.02Hz [4], 0.03Hz [4], 0.17Hz [7], 1Hz [11], 1.25Hz [2] 2.5Hz [1][2], [6], 25Hz [2], [6], 40Hz [12], and 250Hz [1], [6]). However, the minimum-ac-impedance frequency for SRC charging (1kHz [22], and 410Hz [23]) is relatively higher than the frequency for pulse charging. Also, since the SRC has a momentary zero condition, the zero current condition is too short to distribute the ions evenly.…”

“…As a result, in [22], it was shown that the SRC charging improves the charging time without the constant voltage (CV) phase by about 742 seconds (17%) and reduces the rising temperature by approximately 2 °C (45.5%) in comparison with the traditional CC-CV charging. Also, in [23], it was shown that the SRC charging improves the charging time with the CV phase by about 534 seconds (17%) and reduces the battery temperature by about 1.8 °C (5%) in comparison with the CC-CV charging. However, since a battery is charged by not alternating current (ac) but DC, the DC component should have been considered in the SRC charging.…”

“…New charging techniques are introduced to use the frequency where the battery impedance reaches a minimum in EIS [22]- [23]. This frequency is called the minimum-ac-impedance frequency.…”

Design aspects of an experimental setup for investigating current ripple effects in lithium-ion battery cells

“…Triggered by this new data, one can naturally question the boundaries of such a statement and, in particular, question the effects of frequency and amplitude of the ripple current when put in different SMPC contexts. Additionally, it has been demonstrated in [5,6] that by charging a liion battery with a specified imposed current ripple, charging efficiency and lifetime expectancy can be improved. From [2][3][4][5][6], one can conclude that there are different perspectives, as well as different contexts that should be linked together, and questions that should be addressed with appropriate data.…”

“…Additionally, it has been demonstrated in [5,6] that by charging a liion battery with a specified imposed current ripple, charging efficiency and lifetime expectancy can be improved. From [2][3][4][5][6], one can conclude that there are different perspectives, as well as different contexts that should be linked together, and questions that should be addressed with appropriate data. With this motivation, an experimental setup, allowing for testing the effect of ripple currents on li-ion battery cells, has been designed and is currently under construction in a joint project of KTH and Scania AB.…”