Batteries, high rate performance

The need to develop high rate performance electrodes [116] in advanced batteries, such as rocking-chair (lithium-ion) cells [117], has led to efforts... 

Nickel-cadmium batteries with thin sintered plates are used for on-board power supplies in aircraft, helicopters, tanks and military vehicles where their excellent low temperature, high rate performance is an important attribute. Modern 40 Ah cells designed for airborne use can deliver 20 kW of instantaneous power at 25°C and over 10 kW at —30DC. Again, the high cost of this system compared with that of lead-acid batteries has restricted its use. 

To get high-rate performance in Li-ion batteries, Moriguchi et al. [209] have studied the nanocomposite of Ti02 and CNTs. SWCNT-containing mesoporous Ti02 has shown better rate performance compared to that of the Ti02 without CNTs. 

E. Meissner, Brite/Euram Project BE7297, Task I, Effect of electronically conducting additives to the positive active material on high-rate performance of lead-acid batteries. Final Report, 1 January 1994 to 31 December 1997, Advanced Lead-Acid Battery Consortium, Research Triangle Park, NC, USA, 1998. 

Jo, M., Y.S. Hong, J. Choo, and J. Cho (2009). Effect of LiCoO Cathode Nanoparticle Size on High Rate Performance for Li-Ion Batteries. Journal of the Electrochemical Society 156, A430. 

A. S. Peiakash et al, Solution-combustion synthesized nanocrystalhne Li4Ti50i2 as high-rate performance Li-ion battery anode , Chemistry of Materials, 22 (9), pp. 2857-2863, 2010. 

Zhang B, Liu Y, Huang Z, Oh S, Yu Y, Mai YW, Kim JK (2012) Urchin-like Li4 Ti5012-carbon nanofiber composites for high rate performance anodes in Li-ion batteries. J Mater Chem 22 12133-12140... 

The electrolyte can be fabricated in the form of a thin solid film, thereby eliminating the need of a separator element requirement. The very thin electrolyte, combined with a thin electrode structures, could allow electrode high rate performance and improved lithium everlasting morphology. The possibility of greater intrinsic safety combined with improved rate capability makes the polymer electrolyte battery system a viable candidate for a high-performance battery. Major advantages of polymer electrolyte batteries can be summarized as follows ... 

The incorporation of lithium ion in a sohd electrolyte yields higher pellet conductivity and significantly improved high-rate performance of the solid-state rechargeable battery cells. 

Recent emphasis on the performance of the primary alkaline manganese dioxide battery has been directed toward improving its high-rate performance to meet the requirements of the new digital cameras and other portable electronics. The new high-rate (Ultra or Premium) battery was first sold in 2000 and already commands about 25% of the market. 

The second design is the spirally wound electrode construction, typically used in sealed portable rechargeable batteries and high-rate primary and rechargeable lithium batteries (Fig. 3.2lb). In this design, the electrodes are prepared as thin strips and then rolled, with a separator in between, into a jelly roll and placed into the cylindrical can. This design emphasizes surface area to enhance high-rate performance, but at the expense of active material and capacity. 

In Fig. 3.22 the performance of a battery designed for high-rate performance is compared with one using the same electrochemieal system, but optimized for capacity. The high-rate batteries have a lower eapacity but deliver a more constant performance as the discharge rate inereases. 

Alkaline (Zn/alkaline/MnOj) Most popular general-purpose premium battery good low-temperature and high-rate performance moderate cost Most popular primary-battery used in a variety of portable battery operated equipments... 

The ordinary Leclanchd cell uses a mixture of ammonium chloride and zinc chloride, with the former predominating. Zinc-chloride cells typically use only Z11CI2, but can contain a small amount of NH4CI to ensure high rate performance. Eixamples of typical electrolyte formulation for the zinc-carbon battery systems are listed in Table 8.3. 

Good high-rate performance—suitable for engine starting (but outperformed by some nickel-cadmium and nickel metal-hydride batteries)... 

The energy density of the flat-pasted positive-plate and the tubular positive-plate batteries is similar. It is lower for the Plants positive-plate batteries. The high-rate performance of the flat-pasted positive cells is better because these plates can be made thinner than the tubular or Plants plates. 

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