A systematic approach to the analysis and design of a bi-directional Cûk converter for the cell voltage balancing control of a series-connected lithium-ion battery string is presented in this paper. The proposed individual cell equalizers (ICE) are designed to operate at discontinuous-capacitor-voltage mode (DCVM) to achieve the zero-voltage switching (ZVS) for reducing the switching loss of th...

Lithium ion secondary batteries have a high voltage and a high energy density, as shown in Fig. 1, and are widely used in mobile devices such as cell phones, notebook PCs and PDAs. However, since lithium ion secondary batteries use a flammable organic liquid electrolyte, there is a risk of explosion or fire. Fire accidents can also occur due to contamination during production or from overchargi...

OVERVIEW: As regards the expansion of “ubiquitous networks,” as the functionality of mobile information devices improves, the power source of such devices must also be improved. At present, to boost the performance of the lithium-ion battery commonly used today, new technical innovations regarding anode and cathode materials are necessary. In accordance with these needs, Hitachi is engaged in d...

With the mass market penetration of electric vehicles, the Greenhouse Gas (GHG) emissions associated with lithium-ion battery production has become a major concern. In this study, by establishing a life cycle assessment framework, GHG emissions from the production of lithium-ion batteries in China are estimated. The results show that for the three types of most commonly used lithium-ion batteri...

The initial lithium loss during the formation stage is a critical issue that significantly reduces the specific capacity and energy density of current rechargeable lithium-ion batteries (LIBs). An effective strategy to solve this problem is using electrode prelithiation additives that can work as a secondary lithium source and compensate the initial lithium loss. Herein we show that nanocomposi...

The optimal profile of charging current for a lithium-ion battery is estimated using dynamic optimization implemented via control vector parameterization (CVP). An efficient reformulated model is used for simulating the system behavior of the Li-ion battery. Dynamic optimization is made possible due to the computationally inexpensive reformulated model. It is found that, if the battery is charg...

Anatase TiO2 is a stable, cheap, non-toxic and environmentally benign candidate for use as an anode active material for lithium ion batteries (LIB). Due to the comparably high lithium insertion potential of around 1.8 V vs. Li/Li, typical battery electrolytes can be used in their thermodynamic stability window. Anatase offers high capacity and high cycling stability, and due to the oxidic frame...

Resource depletion aspects are repeatedly used as an argument for a shift towards new battery technologies. However, whether serious shortages due to the increased demand for traction and stationary batteries can actually be expected is subject to an ongoing discussion. In order to identify the principal drivers of resource depletion for battery production, we assess different lithium-ion batte...

Lithium-iron-orthosilicate is one of the most promising cathode materials for Li-ion batteries due to its safety, environmental brightness and potentially low cost. In order to produce a low cost cathode material, Li2FeSiO4/C samples are synthesized via sol-gel (SG; one sample) and solid state (SS; two samples with different carbon content), starting from Fe (III) in the raw materials (lo...