An Aqueous Rechargeable Lithium Battery with Good Cycling Performance

Abstract

The development of the world economy and the consequent increase in traffic means that increasing numbers of heavy fuel-powered vehicles are appearing on our roads, resulting in greater pollution of the environment. Electric vehicles (EVs) are a new, developing trend in the world automotive industry, and an important tool for reducing CO 2 emissions and protecting the environment. EVs must first and foremost be safe and reliable, and must operate with acceptable costs. Unfortunately, thus far, few kinds of batteries can meet all the requirements for EVs. [1][2][3][4][5][6][7][8] In the case of lithium-ion batteries, their use in EVs is still handicapped by significant safety problems, although their other performance attributes are often satisfactory. The main problem is that they use flammable organic electrolytes, which cannot withstand improper use, such as overcharging or short-circuiting, although much effort has been expended in this direction. [4] The development of new types of "green" battery materials and safer, less-expensive rechargeable systems is therefore necessary.In the mid 1990s, a new type of rechargeable lithium-ion battery with an aqueous electrolyte was reported. [9,10] This battery uses lithium-intercalation compounds such as LiMn 2 O 4 , LiNi 0.81 Co 0.19 O 2 , and VO 2 as the electrode material and an alkaline or neutral aqueous electrolyte, [9][10][11] and can overcome the disadvantages of nonaqueous lithium-ion batteries, such as high cost and safety problems. However, since its cycling was reported to be very poor it failed to attract strong interest from researchers.Here we report that an aqueous rechargeable lithium battery (ARLB) with LiCoO 2 as the positive electrode, LiV 3 O 8 as the negative electrode, and saturated LiNO 3 solution as the electrolyte shows good cycling and therefore shows promise as a power source for safe EVs.The cyclic voltammograms of LiV 3 O 8 and LiCoO 2 in saturated LiNO 3 aqueous electrolyte are shown in Figure 1. In the case of LiV 3 O 8 , there is one pair of redox peaks located at À0.19 (red. 1) and 0.098 V (ox. 1) versus a saturated calomel electrode (SCE), which is evidently due to the intercalation and deintercalation reaction accompanying gain and loss of an electron. The average redox potential is À0.046 V (versus SCE). Since hydrogen evolution was observed at a more negative potential due to overpotential (ca. À1.0 V versus SCE), it is clear that LiV 3 O 8 is very stable in this aqueous electrolyte and can be used as a negative electrode material without significant hydrogen evolution. LiCoO 2 also exhibits one pair of Li + intercalation and deintercalation peaks at 0.8 (red. 2) and 1.35 V (ox. 2) versus SCE, respectively (average redox potential of 1.075 V versus SCE). These voltages are also lower than that for oxygen evolution, which is at approximately 1.8 V versus SCE. This illustrates that the positive electrode is also stable in this aqueous solution.The charge and discharge curves of LiV 3 O 8 //LiCoO 2 cells in the first cycle in organic ...

A study of the lithium intercalation into nanoparticles of LiCoO2 from an aqueous solution

“…The discharge capacity of LiCoO 2 nanoparticles was achieved to be 90 mAh/g and the electrode material exhibits[95 % Columbic efficiency. This value is greater than the values, which have been reported for LiCoO 2 in aqueous electrolytes [4,17].…”

“…The electrochemical properties of LiCoO 2 were also studied in nonaqueous solutions [15,16]. Some other researches designed rechargeable lithium batteries based on this material using aqueous solutions [1,3,17]. However, a detailed study on the intercalation of lithium ion in this oxide from an aqueous solution is lacking.…”

Electrochemical performance of B and M phases VO2 nanoflowers

“…The above data show that the discharge capacities of the VO 2 (B) nanoflowers is comparable to those reported for VO 2 (B) nanostructures [12,13], in the meanwhile, the shape of the curve for the B phase sample is exhibiting a flat plateau in the middle of the capacity range, which is similar to the reported result by Wang group [14], referring to lithium-ion de-intercalation and intercalation reactions.…”

Full open-framework batteries for stationary energy storage

“…Very few of the transition metal oxides and phosphates typically used to intercalate Li þ and Na þ have reaction potentials between -0.5 V and 0 V vs SHE, the optimal range for anodes in aqueous electrolytes 32 . Some, such as VO 2 and LiV 3 O 8 , are partially soluble 33 . If the anode potential is slightly too low, as in the case of the NASICON A 1 þ x Ti 2 (PO 4 ) 3 (A ¼ Li, Na), then the low coulombic efficiency of the anode will result in overcharge of the cathode, unless the cathode potential is tuned to result in commensurate O 2 evolution 34 .…”