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Jeff Dahn Research Group

UHPC Studies of typical additives

Measuring the Impact of Additives using High Precision Coulometry

The b) panel of the Figure shows that electrolyte additives improve the cycle life of Li-ion cells.  Using the High Precision Charger (HPC) to accurately measure coulombic efficiency allows cell lifetimes to be projected after only a few weeks of cycling 1-4.  In the a) panel below, the coulombic efficiency increases from control, to FEC, to VC, to VC+FEC+VEC+PS, just as the cycle life does in the right panel.  The HPC measurements can be made in a few weeks while the cycling tests can take many months.

Figure 1 - Coulombic efficiency
VC = vinylene carbonate, FEC = fluoroethylene carbonate, VEC = vinyl ethylene carbonate, PS = 1,3 propane sultone

References

  1. J.C. Burns, G. Jain, A. Smith, K. Eberman, E. Scott, J. Gardner and J.R. Dahn, J. Electrochem. Soc., 158, A255-A261 (2011).
  2. J.C. Burns, N.N. Sinha, D.J. Coyle, G. Jain, C.M. VanElzen, W.M. Lamanna, A. Xiao, E. Scott, J.P. Gardner, and J.R. Dahn, J. Electrochem. Soc., 159, A85-A90 (2012).
  3. J.C. Burns, N.N. Sinha, Gaurav Jain, Hui Ye, Collette M. VanElzen, W.M. Lamanna, A. Xiao, Erik Scott, J. Choi, and J.R. Dahn, J. Electrochem. Soc., 159, A1095-A1104 (2012).
  4. J.C. Burns, N.N. Sinha, Gaurav Jain, Hui Ye, Collette M. VanElzen, W.M. Lamanna, A. Xiao, Erik Scott, J. Choi, and J.R. Dahn, J. Electrochem. Soc., 159, A1105-A1113 (2012).