Lithium metal batteries are nonrechargeable primary batteries that have metallic lithium as an anode. The name refers to the metal to distinguish them from rechargeable lithium-ion batteries, which use lithiated metal oxides as the cathode material. Although most lithium metal batteries are non-rechargeable, rechargeable lithium metal batteries are also under development. Since 2007, Dangerous Goods Regulations differentiate between lithium metal batteries (UN 3090) and lithium-ion batteries (UN 3480).
They stand apart from other batteries in their high charge density and high cost per unit. Depending on the design and chemical compounds used, lithium cells can produce voltages from (comparable to a zinc–carbon or alkaline battery) to about .
Disposable primary lithium batteries must be distinguished from secondary lithium-ion or a lithium-polymer,Batscap - La batterie lithium métal polymère in batscap.com which are rechargeable batteries and contain no metallic lithium. Lithium metal batteries, by contrast, are defined by the use of metallic lithium as the anode. Pure lithium will instantly react with water, or even moisture in the air; the lithium in lithium-ion batteries is a less reactive compound.
Lithium batteries are widely used in portable consumer electronic devices. The term "lithium battery" refers to a family of different lithium-metal chemistries, comprising many types of cathodes and electrolytes but all with metallic lithium as the anode. The battery requires from 0.15 to 0.3 kg (5 to 10 oz) of lithium per kWh. As designed these primary systems use a charged cathode, that being an electro-active material with crystallographic vacancies that are filled gradually during discharge.
The most common type of lithium cell used in consumer applications uses metallic lithium as the anode and manganese dioxide as the cathode, with a salt of lithium dissolved in an organic solvent as the electrolyte.
History
Chemistries
This table is dominated by lithium-ion, not lithium-metal, chemistries—it's inclusive rather than focused on the specific topic of lithium metal batteries.
Chemistry Cathode Electrolyte Nominalvoltage Open-circuitvoltage Wh/kg Wh/L Li–MnO2(IEC code: C),"CR" Heat-treated manganese dioxide Lithium perchlorate in an organic solvent (propylene carbonate and dimethoxyethane in many common cells) 3 V 3.3 V 280 580 "Li–Mn". The most common consumer-grade lithium battery, about 80% of the lithium battery market. Uses inexpensive materials. Suitable for low-drain, long-life, low-cost applications. High energy density per both mass and volume. Operational temperature ranges from -30 °C to 60 °C. Can deliver high pulse currents. With discharge, the internal impedance rises and the terminal voltage decreases. High self-discharge at high temperatures. 1,2-Dimethoxyethane is a REACH candidate substance of very high concern. Li–(CF)x(IEC code: B),"BR" Carbon monofluoride Lithium tetrafluoroborate in propylene carbonate, dimethoxyethane, or gamma-butyrolactone 3 V 3.1 V 360–500 1,000 Cathode material formed by high-temperature intercalation of fluorine gas into graphite powder. Compared to manganese dioxide (CR), which has the same nominal voltage, it provides more reliability. Used for low to moderate current applications in memory and clock backup batteries. Used in aerospace applications, qualified for space since 1976, military applications both terrestrial and marine, in missiles, and in artificial cardiac pacemakers. Operates up to around 80 °C. Very low self-discharge (<0.5%/year at 60 °C, <1%/yr at 85 °C). Developed in the 1970s by Matsushita. Li–FeS2(IEC code: F),"FR" Iron disulfide Propylene carbonate, dioxolane, dimethoxyethane 1.4–1.6 V 1.8 V 297 "Lithium-iron", "Li/Fe". Called "voltage-compatible" lithium, it can work as a replacement for alkaline batteries with its 1.5 V nominal voltage. As such, Energizer lithium cells of AA and AAA size employ this chemistry. 2.5 times higher lifetime for high current discharge regime than alkaline batteries, better storage life due to lower self-discharge(10–20 years). FeS2 is cheap. Cathode is often designed as a paste of iron sulfide powder mixed with powdered graphite. Variant is Li–CuFeS2. Li–SOCl2(IEC code: E) Thionyl chloride Lithium tetrachloroaluminate in thionyl chloride 3.5 V 3.65 V 500–700 1,200 Liquid cathode. For low-temperature applications. Can operate down to −55 °C, where it retains over 50% of its rated capacity. A negligible amount of gas generated in nominal use, a limited amount under abuse. Has relatively high internal impedance and limited short-circuit current. High energy density, about 500 Wh/kg. Toxic. Electrolyte reacts with water. Low-current cells are used for portable electronics and memory backup. High-current cells are used in military applications. In long storage, forms passivation layer on the anode, which may lead to temporary voltage delay when put into service. High cost and safety concerns limit use in civilian applications. Can explode when shorted. Underwriters Laboratories require a trained technician for the replacement of these batteries. Hazardous waste, Class 9 Hazmat shipment. Not used for consumer or general-purpose batteries. Li–SOCl2,BrCl, Li–BCX(IEC code: E) Thionyl chloride with bromine chloride Lithium tetrachloroaluminate in thionyl chloride 3.7–3.8 V 3.9 V 350 770 Liquid cathode. A variant of the thionyl chloride battery, with 300 mV higher voltage. The higher voltage drops back to 3.5 V soon as the bromine chloride gets consumed during the first 10–20% of the discharge. The cells with added bromine chloride are thought to be safer when abused. Li–SO2Cl2(IEC code: Y) Sulfuryl chloride Lithium tetrachloroaluminate in sulfuryl chloride 3.7 V 3.95 V 330 720 Liquid cathode. Similar to thionyl chloride. Discharge does not result in a build-up of elemental sulfur, which is thought to be involved in some hazardous reactions, therefore sulfuryl chloride batteries may be safer. Commercial deployment is hindered by the tendency of the electrolyte to corrode the lithium anodes, reducing the shelf life. Chlorine is added to some cells to make them more resistant to abuse. Sulfuryl chloride cells give less maximum current than thionyl chloride ones, due to polarization of the carbon cathode. Sulfuryl chloride reacts violently with water, releasing hydrogen chloride and sulfuric acid. Li–SO2(IEC code: W) Sulfur dioxide on teflon-bonded carbon Lithium bromide in sulfur dioxide with small amount of acetonitrile 2.85 V 3.0 V 250 400 Liquid cathode. Can operate down to −55 °C and up to +70 °C. Contains liquid SO2 at high pressure. Requires safety vent, can explode in some conditions. High energy density. High cost. At low temperatures and high currents, performs better than Li–MnO2. Toxic. Acetonitrile forms lithium cyanide, and can form hydrogen cyanide in high temperatures. Used in military applications.