Suppressing HF cable oscillations during dynamic measurements of cells and batteries

Apparatus employing time-varying signals to test an electrochemical cell or battery comprising:

• measuring circuitry containing current-excitation circuitry and voltage-sensing circuitry, said current-excitation circuitry adapted to couple to said cell or battery with an A-B conductor pair and said voltage-sensing circuitry adapted to couple to said cell or battery with a separate C-D conductor pair,
• a four-wire cable section connected to said measuring circuitry, said four-wire cable section comprising said A-B conductor pair and said C-D conductor pair bound together in close proximity to one-another within the same four-wire cable section, wherein A-B conductor pair and the C-D conductor pair of the four-wire cable section acts as a transmission line at high frequency and introduces an impedance mismatch between the four-wire cable section and the measurement circuitry,
• a spaced-apart cable section interconnecting said four-wire cable section with positive and negative terminals of said electrochemical cell or battery, wherein the A-B conductor pair and the C-D conductor pair in the spaced apart cable section acts as a transmission line at high frequency and introduces an impedance mismatch between the spaced apart cable section and said electrochemical cell or battery;
• and,
• one or more magnetic cores placed upon said A-B conductor pair, said magnetic cores suppressing high-frequency reflected waves oscillating on a two-wire transmission line comprising said A-B conductor pair due to said impedance mismatches.

Apparatus employing time-varying signals to test an electrochemical cell or battery comprising:

• measuring circuitry containing current-excitation circuitry and voltage-sensing circuitry, said current-excitation circuitry adapted to couple to said cell or battery with an A-B conductor pair and said voltage-sensing circuitry adapted to couple to said cell or battery with a separate C-D conductor pair,
• a four-wire cable section connected to said measuring circuitry, said four-wire cable section comprising said A-B conductor pair and said C-D conductor pair bound together in close proximity to one-another within the same four-wire cable section, wherein A-B conductor pair and the C-D conductor pair of the four-wire cable section acts as a transmission line at high frequency and introduces an impedance mismatch between the four-wire cable section and the measurement circuitry,
• a spaced-apart cable section interconnecting said four-wire cable section with positive and negative terminals of said electrochemical cell or battery, wherein the A-B conductor pair and the C-D conductor pair in the spaced apart cable section acts as a transmission line at high frequency and introduces an impedance mismatch between the spaced apart cable section and said electrochemical cell or battery;
• and,
• a bypass capacitor connected directly across said C-D conductor pair said bypass capacitor suppressing high-frequency reflected waves oscillating on a two-wire transmission line comprising said C-D conductor pair due to said impedance mismatches.

Apparatus employing time-varying signals to test an electrochemical cell or battery comprising:

• measuring circuitry containing current-excitation circuitry and voltage-sensing circuitry, said current-excitation circuitry adapted to couple to said cell or battery with an A-B conductor pair and said voltage-sensing circuitry adapted to couple to said cell or battery with a separate C-D conductor pair,
• a four-wire cable section connected to said measuring circuitry, said four-wire cable section comprising said A-B conductor pair and said C-D conductor pair bound together in close proximity to one-another within the same four-wire cable section, wherein A-B conductor pair and the C-D conductor pair of the four-wire cable section acts as a transmission line at high frequency and introduces an impedance mismatch between the four-wire cable section and the measurement circuitry,
• a spaced-apart cable section interconnecting said four-wire cable section with positive and negative terminals of said electrochemical cell or battery, wherein the A-B conductor pair and the C-D conductor pair in the spaced apart cable section acts as a transmission line at high frequency and introduces an impedance mismatch between the spaced apart cable section and said electrochemical cell or battery;
• and,
• one or more magnetic cores placed upon said C-D conductor pair, said magnetic cores suppressing high-frequency reflected waves oscillating on a two-wire transmission line comprising said C-D conductor pair due to said impedance mismatches.

Apparatus employing time-varying signals to test an electrochemical cell or battery comprising:

• measuring circuitry adapted to couple to said cell or battery with separate current-carrying and voltage-sensing conductors,
• a Kelvin cable interposed between said measuring circuitry and said cell or battery, said Kelvin cable comprising a pair of current-carrying conductors and a pair of voltage-sensing conductors, said pair of
• voltage-sensing conductors
• possessing a particular characteristic impedance value;
• and,
• a blocking capacitor and a resistor connected in series across said pair of voltage-sensing conductors at an interface between said measuring circuitry and said Kelvin cable, said resistor having a value essentially equal to said particular characteristic impedance value.

Apparatus employing time-varying signals to test an electrochemical cell or battery comprising:

• measuring circuitry adapted to couple to said cell or battery with separate current-carrying and voltage-sensing conductors,
• a four-wire cable section interfaced with said measuring circuitry, said four-wire cable section comprising a pair of current-carrying conductors and a pair of voltage-sensing conductors, said pair of voltage-sensing conductors possessing a particular characteristic impedance value,
• a spaced-apart cable section interposed between said four-wire cable section and said cell or battery, said spaced-apart cable section possessing a pair of voltage-sensing conductors that separately contact positive and negative terminals of said cell or battery;
• and,
• one or more resistances connected in series with said voltage sensing conductors in said spaced-apart cable section, said resistances being essentially equal in sum value to said particular characteristic impedance value.