In:
Energy Technology, Wiley, Vol. 2, No. 3 ( 2014-03), p. 257-262
Abstract:
In this study spinel‐lithium manganese oxide (LiMn 2 O 4 ) powders were prepared by using a simple sol–gel method with polyvinyl alcohol (PVA), and further combined with a conductive additive, graphene, to produce a composite electrode material for improved performance. The effects of the variation in the ratios of binder (PVA) to LiMn 2 O 4 precursor on the particle size and electrochemical behavior of the composite were studied. Particle sizes of 〈 200 nm were obtained. An energy density of 17.36 Wh kg −1 was obtained at an operating voltage of 3.2 V for the pure LiMn 2 O 4 sample tested against a graphene electrode. For simultaneously improving power density (current Li batteries have a low power density as a disadvantage) along with energy density, the LiMn 2 O 4 –graphene composite was chosen as an electrode material. LiMn 2 O 4 –graphene composite electrodes were prepared by electrophoretic co‐deposition. The ratio of LiMn 2 O 4 –graphene composite was optimized to 1:1 during the electrode study based on its electrochemical performance. An average energy density of 30 Wh kg −1 , a specific capacity of 49 mAh g −1 , and an enhanced power density of 800 W kg −1 at a discharge current of 0.5 A g −1 were obtained. Discharge behavior improved evidently for tests performed on composite electrodes with increased LiMn 2 O 4 (1:1.3 graphene/LiMn 2 O 4 ). An improved average energy density of 59.6 Wh kg −1 was obtained along with a power density of 697 W kg −1 . The electrodes showed good performance during study of a button cell device. Such electrodes are well suited for hybrid energy storage devices having good energy and power density and bridging the gap between batteries and supercapacitors.
Type of Medium:
Online Resource
ISSN:
2194-4288
,
2194-4296
DOI:
10.1002/ente.201300120
Language:
English
Publisher:
Wiley
Publication Date:
2014
detail.hit.zdb_id:
2700412-0
detail.hit.zdb_id:
2700999-3
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