The hybrid battery system includes a primary battery pack, a secondary battery pack, a battery control unit, a battery pack positive terminal, and a battery pack negative terminal. The battery control unit includes a management module and a variable resistor. The primary battery pack supplies power at lower temperatures, while the secondary battery pack supplies power at higher temperatures. The primary battery pack is unsafe at higher temperatures, and the primary cells within the primary battery pack are modified to mitigate the dangers that previously rendered the primary battery pack unusable in a hybrid battery pack at higher temperatures. The invention includes the method of safely operating the hybrid battery system with the modified primary battery cells of the primary battery pack.

The hybrid battery system includes a primary battery pack, a secondary battery pack, a battery control unit, a battery pack positive terminal, and a battery pack negative terminal. The battery control unit includes a management module and a variable resistor. The primary battery pack supplies power at lower temperatures, while the secondary battery pack supplies power at higher temperatures. The primary battery pack is unsafe at higher temperatures, and the primary cells within the primary battery pack are modified to mitigate the dangers that previously rendered the primary battery pack unusable in a hybrid battery pack at higher temperatures. The invention includes the method of safely operating the hybrid battery system with the modified primary battery cells of the primary battery pack.

A drill pipe string conveyed retrievable plug system has a central through bore. The plug system includes a drill pipe string; a control section; a running tool with a connector at a lower end of a drill pipe string with the control section, and a top connector on a mechanical plug section with a bridge plug. The mechanical plug section includes a mandrel with the through bore, a ball valve arranged for closing the through bore, and a packer sleeve on the mandrel with slips and a packer element. The control section includes an electric supply, an electric control unit, and sensors connected to the electric control unit. The mechanical plug section includes a motor controlled by the electrical control unit. The motor is arranged to turn a selector ring to a selected first rotational position so as for allowing a piston sleeve to slide to an axial first stop position in order for opening to fluid channels through the mandrel from the through bore to the packer sleeve. The pressure in the through bore can be set to the pressure of the packer sleeve in a surrounding casing.

Methods for determining water-filled porosity using a general volumetric mixing law and the measurements of a dielectric tool are described. The water-filled porosity estimates are used to obtain water salinity estimates and the optimal parameters of the volumetric mixing law. These estimates are in turn used to generate novel quality indicators.

Methods for determining water-filled porosity using a general volumetric mixing law and the measurements of a dielectric tool are described. The water-filled porosity estimates are used to obtain water salinity estimates and the optimal parameters of the volumetric mixing law. These estimates are in turn used to generate novel quality indicators.

A method for identifying zones in an annulus with poor cementing that may include deploying a fiber optic cable within the wellbore, creating a temperature gradient in the wellbore, and collecting temperature data over a period of time as the wellbore returns to a thermal equilibrium. The method may also include comparing the temperature data collected by the fiber optic cable at one or more locations to predicted temperature data over the period of time at the one or more locations to identify locations where the measured temperature data deviates from the predicted temperature data for identifying locations or zones of the annulus that have poor cementing.

A method for identifying zones in an annulus with poor cementing that may include deploying a fiber optic cable within the wellbore, creating a temperature gradient in the wellbore, and collecting temperature data over a period of time as the wellbore returns to a thermal equilibrium. The method may also include comparing the temperature data collected by the fiber optic cable at one or more locations to predicted temperature data over the period of time at the one or more locations to identify locations where the measured temperature data deviates from the predicted temperature data for identifying locations or zones of the annulus that have poor cementing.

Method and system for developing reservoirs, such as hydrocarbon reservoirs or aquifers, including correcting pressure transient test data to account for variations of fluid density between a gauge depth and a mid-reservoir depth in a wellbore. Gauge depth pressure and temperature measurements, and density correlations are used to estimate mid-reservoir depth pressures, which can be used in a pressure transient analysis.

Method and system for developing reservoirs, such as hydrocarbon reservoirs or aquifers, including correcting pressure transient test data to account for variations of fluid density between a gauge depth and a mid-reservoir depth in a wellbore. Gauge depth pressure and temperature measurements, and density correlations are used to estimate mid-reservoir depth pressures, which can be used in a pressure transient analysis.

The present invention provides an intelligent geophysical data acquisition system and acquisition method for shale oil and gas optical fiber. A pipe string is arranged in a metal casing, and an external armored optical cable is fixed outside the metal casing; an, internal armored optical cable is fixed outside the pipe string; the external armored optical cable comprises a downhole acoustic sensing optical cable, two multi-mode optical fibers, a strain optical cable and a pressure sensor array, and further comprises horizontal ground acoustic sensing optical cables arranged in the shallow part of the ground according to an orthogonal grid, and artificial seismic source excitation points arranged on the ground according to the orthogonal grid.