A discharge prevention system for a primary battery comprises an energy harvesting module that produces energy from an environment and a control circuit for applying electrical current to the primary battery from the energy harvesting module to prevent or reduce self-discharge. This system will prevent or reduce rapid self-discharge at high temperatures in lithium-based primary batteries, for example. It can significantly extend the operating lifetime of such batteries operating at high temperature, particularly in applications where battery power is used intermittently. Specifically, a very low current is supplied to the primary battery at high temperature, significantly extending its storage lifetime. In some cases, depending on the current characteristics of the battery, the energy associated with the bias current can be in the same order of magnitude as the energy that would be lost by self-discharge, but in many cases it is much lower. This bias current “biases” the battery in such a way that self-discharge current of the primary battery is minimized.

A redox flow battery is described that does not include an ion exchange resin such as a proton exchange membrane but rather uses a generally stationary separator liquid that separates the anolyte from the catholyte at immiscible liquid-liquid interfaces. Solvents and electrochemically active components of the anolyte and catholyte would not cross the liquid-liquid interfaces between the separator liquid and the anolyte and catholyte, but certain ions in each of the anolyte and catholyte would cross the interface during charging and discharging of the redox flow battery. The separator liquid comprises a relatively small total volume of liquid in such a flow battery arrangement as compared to the anolyte and catholyte. Suitable chemical options are described along with system options for utilizing immiscible phases.

A redox flow battery is described that does not include an ion exchange resin such as a proton exchange membrane but rather uses a generally stationary separator liquid that separates the anolyte from the catholyte at immiscible liquid-liquid interfaces. Solvents and electrochemically active components of the anolyte and catholyte would not cross the liquid-liquid interfaces between the separator liquid and the anolyte and catholyte, but certain ions in each of the anolyte and catholyte would cross the interface during charging and discharging of the redox flow battery. The separator liquid comprises a relatively small total volume of liquid in such a flow battery arrangement as compared to the anolyte and catholyte. Suitable chemical options are described along with system options for utilizing immiscible phases.

The present invention is intended to provide a gel-type solid electrolyte having flexibility while maintaining the advantages of an ionic liquid by effectively internalizing the ionic liquid into a porous metal oxide. To this end, the present invention provides the gel-type solid electrolyte which includes an ionic liquid in a porous metal oxide prepared from a silane compound represented by the following Chemical Formula 1:
Si(R.sub.1).sub.x(OR.sub.2).sub.y(CR.sub.3═CR.sub.4R.sub.5).sub.(4-x-y)  [Chemical Formula 1] in the Formula, R.sub.1 and R.sub.2 are alkyl groups with carbon numbers in the range of 1 to 3, which are independent from each other; R.sub.3, R.sub.4 and R.sub.5 are each independently hydrogen, a halogen element or an alkyl group having 1 to 5 carbon atoms; and x is an integer in the range of 0≦x≦3, y is an integer in the range of 1≦y≦4 and x+y is an integer in the range of 2≦x+y≦4.

Provided is a system and medical device that includes self diagnosing control switches. The control switch may be slidable within a slot in order to control activation of some function of the medical device. Due to natural wear and tear of movement of a control switch, the distances along the sliding slot that correspond to how much energy is used for the function may need to be adjusted over time in order to reflect the changing physical attributes of the actuator mechanism. The self diagnosing control switches of the present disclosures may be configured to automatically adjust for these thresholds using, for example, Hall effect sensors and magnets. In addition, in some cases, the self diagnosing control switches may be capable of indicating external influences on the controls, as well as predict a time until replacement is needed.

An electrochemical cell that converts chemical energy to electrical energy includes a cathode with an active material of fluorinated carbon on a perforated metal cathode current collector, a lithium anode on a perforated metal anode current collector, a stepped header, a stable electrolyte, and a separator. In various embodiments, an anode current collector design, a cathode current collector design, a stepped header design, a cathode formulation, an electrolyte formulation, a separator, and a battery incorporating the electrochemical cell are provided.

A lithium primary battery includes a wound electrode body obtained by winding a sheet-like positive electrode, a sheet-like negative electrode, and a separator interposed between the positive electrode and the negative electrode, and a nonaqueous electrolyte solution. The positive electrode includes manganese dioxide as a positive electrode active material. The negative electrode includes at least one selected from the group consisting of metallic lithium and lithium alloys, and has a first principal surface and a second principal surface opposite to the first principal surface. An entire surface of each of the first principal surface and the second principal surface faces the positive electrode. A total area of the first principal surface and the second principal surface is 100 cm.sup.2 or more and 180 cm.sup.2 or less.

A lithium primary battery includes a wound electrode body obtained by winding a sheet-like positive electrode, a sheet-like negative electrode, and a separator interposed between the positive electrode and the negative electrode, and a nonaqueous electrolyte solution. The positive electrode includes manganese dioxide as a positive electrode active material. The negative electrode includes at least one selected from the group consisting of metallic lithium and lithium alloys, and has a first principal surface and a second principal surface opposite to the first principal surface. An entire surface of each of the first principal surface and the second principal surface faces the positive electrode. A total area of the first principal surface and the second principal surface is 100 cm.sup.2 or more and 180 cm.sup.2 or less.

Provided is pouch battery including an electrode assembly, and a case in which the electrode assembly is sealed and housed; the electrode assembly including a stacked structure of a sheet cathode, a sheet separator, and a sheet anode; the sheet cathode including a positive electrode active material disposed on a current collector; the sheet anode is thin conductive sheet on which lithium metal reversibly deposits on a surface thereof during discharging; the sheet anode being made of a conductive material other than lithium and having a surface substantially free from lithium metal prior to charging the battery. The pouch battery design is flexible and lightweight and provides high power density, making it a suitable replacement for conventional lithium-ion primary batteries and thermal batteries in many applications. Power can be further increased by the application of external compression. Additives and formation conditions can be tailored for forming a solid-electrolyte interface (SEI).

The present application relates to a positive electrode plate and an electrochemical device. The positive electrode plate includes a current collector, a positive active material layer and a safety coating disposed between the current collector and the positive active material layer, the safety coating including a polymer matrix and a conductive material, wherein the polymer matrix is fluorinated polyolefin and/or chlorinated polyolefin, and when the safety coating and the positive active material layer are collectively referred to as a positive film layer, the positive film layer includes Na ions and/or K ions at a content of 100 ppm or more, and has an absorption peak at 1646 cm.sup.−1 in infrared absorption spectrum. The positive electrode plate may improve safety performance at elevated temperature of the electrochemical device by quickly disconnecting the circuit at high temperature conditions or when an internal short circuit occurs.