System, method, and computer program product for utilizing a fiber bragg grating to detect a gas indicating the onset of thermal runaway

A method for detecting thermal runaway in a battery cell, the method comprising:

• causing a light source to emit light comprising a transmitted spectrum of wavelengths;
• receiving, from a photodiode optically coupled to a sensing fiber, an electrical output corresponding to an intensity of light received at the photodiode,
• wherein the sensing fiber comprises a first end and a second end,
• wherein the sensing fiber is positioned to receive the light emitted by the light source at the first end,
• wherein the sensing fiber is optically coupled to the photodiode at the second end, and
• wherein the sensing fiber comprises a filtering mechanism configured to reflect a portion of the transmitted spectrum of wavelengths of the light, wherein another portion of the spectrum of wavelengths of the light is received by the photodiode through the sensing fiber;
• identifying a gas based on the electrical output of the photodiode;
• and
• detecting thermal runaway in the battery cell based at least in part on identifying the gas, wherein the gas is detected based on comparing the spectrum of wavelengths of the light received by the photodiode, determined from an electrical output of the photodiode, with a spectral signature of the gas, and wherein detection is based on comparing the spectrum of wavelengths received by the photodiode with a stored spectral signature of the gas, and requires that at least two electrical outputs meet respective threshold conditions indicative of the gas.

A computer program product for detecting thermal runaway in a battery cell, the computer program product comprising at least one non-transitory computer-readable storage medium having computer-readable program code portions stored therein, the computer-readable program code portions comprising an executable portion configured to:

• cause a light source to emit light comprising a transmitted spectrum of wavelengths;
• receive, from a photodiode optically coupled to a sensing fiber, an electrical output corresponding to an intensity of light received at the photodiode,
• wherein the sensing fiber comprises a first end and a second end,
• wherein the sensing fiber is positioned to receive the light emitted by the light source at the first end,
• wherein the sensing fiber is optically coupled to the photodiode at the second end, and
• wherein the sensing fiber comprises a filtering mechanism configured to reflect a portion of the transmitted spectrum of wavelengths of the light, wherein another portion of the spectrum of wavelengths of the light is received by the photodiode through the sensing fiber;
• identify a gas based on the electrical output of the photodiode;
• and
• detect thermal runaway in the battery cell based at least in part on identifying the gas, wherein the gas is detected based on comparing the spectrum of wavelengths of the light received by the photodiode, determined from an electrical output of the photodiode, with a spectral signature of the gas, and wherein detection is based on comparing the spectrum of wavelengths received by the photodiode with a stored spectral signature of the gas, and requires that at least two electrical outputs meet respective threshold conditions indicative of the gas.