IEEE 1679.1-2017 pdf download

IEEE 1679.1-2017 pdf download.IEEE Guide for the Characterization and Evaluation of Lithium-Based Batteries in Stationary Applications.
5.2.2 Active materials
The following lists show common commercial materials used in Li-ion cells. Some products use blends of two or more materials. Electrode materials are often referred to by abbreviations, which are provided in parentheses where applicable.
Negative (anode)
— Unstructured/hard carbon
— Layered carbon (graphite) Lithium titanate (LTO)
— Silicon compounds
Positive (cathode)
— Lithium cobalt oxide (LCO)
— Lithium manganese oxide (LMO)
— Lithiated mixed-metal oxide [e.g., lithium nickel-manganese-cobalt oxide (NMC), lithium nickel- cobalt-aluminum oxide (NCA)1
— Lithium iron phosphate (LFP)
Electrolyte
— Lithium hexafluorophosphate (LiPF6) salt in organic carbonate solution
— Lithium tetrafluoroborate (L1BF4) salt in organic carbonate solution
The electrolyte formulation is proprietary to each manufacturer and is critical to the life of the product, particularly regarding the stability of positive materials with high electrode potentials. The formulation can also affect the cell performance, especially at low temperature, and can help to stabilize the solid- electrolyte interphase (see 5.2.3). The electrolyte may also contain additives with specific functions, for example to produce gas during a thermal runaway event, to assist cell venting (see 6.4.1.4).
5.2.3 Material characteristics
The characteristics of the final product vary markedly depending on the materials used. For example, Figure 2 provides a simple comparison of various positive active materials for a range of attributes. Precise material characteristics vary; consult the manufacturer for information on specific products. Better relative performance is indicated by positions at the outside edge of each chart and worse performance by positions towards the center. The listed attributes are as follows:
— Calendar life at 20 °C to 25 °C
— Calendar life at high temperature (>40 °C)
— Capacity availability at low temperature
— Safety of positive active material (see 6.4) Energy density
— Power density
Li-S batteries use lithium metal negatives and sulfur-based positives and typically a polysulfide electrolyte. This technology has much higher specific energy than Li-ion, with about the same energy density. At the time of preparing this document, commercially available Li-S batteries have limited cycle lives and their use is largely limited to specialized applications, such as unmanned aerial vehicles.
5.3 Intended applications
Lithium-based battery systems are suitable for various stationary battery applications with the proper design and safety and electronic control systems. Li-ion cells can be designed and optimized for high- power applications such as uninterruptible power supplies. Alternatively, cells can be optimized for long- duration discharge applications such as telecommunications and renewable energy storage. The resulting battery systems are smaller and lighter than most other battery types, making these lithium-based systems suitable for applications that have limited space and increasing energy requirements.
Li-ion technologies are also suitable for applications involving frequent cycling, including prolonged operation at partial states of charge. For continuous high-rate cycling applications such as frequency regulation for the power grid, such systems often require enhanced thermal management (see 5.8.5).
Many stationary applications require batteries to be idle for extended periods until their energy is required. Special consideration should be given to how Li-ion batteries are charged in these applications (see 5.7).
Because of these issues, it is important that the user verify with the battery supplier that the lithium-based battery selected for use has been designed and is listed for that specific application. Moreover, it is important to recognize that a lithium-based battery that is optimized for one stationary application may not be appropriate or safe to use in a different application.
5.4 Components and construction
5.4.1 General
The intent of this subclause is to provide the user with general knowledge of the types of components used in a lithium-based battery. Because lithium-based batteries arc integrated with electrical and thermal management systems, they are commonly referred to as battery systems. This subclause predominantly describes Li-ion battery systems. Although there are many different chemistry couples as well as different physical formats, the following generic description applies to many commercially available Li-ion designs. Because of the proprietary nature of lithium-based batteries, each battery is typically supplied as a complete system from the vendor and does not require the user to match components or combine cells and auxiliary components.