Battery Pack Ragone Plot

Battery pack Ragone plot is power density versus energy density. There are a number of key battery metrics and this one is great to see where a design sits on the Power vs Energy Density Curve.

Note that the power is the peak power of the pack available for 10s. You could also plot the power as continuous.

In simple terms:

  • Moving to the right on the x-axis is increasing in energy density
  • Moving up the y-axis is increasing the power density

There are a number of factors that make it difficult to engineer a pack with very high power and high energy density.

The main factors are:

  • Power versus Energy density cells
    • thinner anode and cathodes increases power and decreases available energy
  • Cooling more demanding in high power packs and hence increased mass and volume to package (cooling options)
  • Thicker busbars – current carrying capability is proportional to the cross-sectional area
  • High power = High currents => larger fuses and contactors

This post has been built based on the support and sponsorship of: AVANT Future MobilityQuarto Technical ServicesTAE Power Solutionsh.e.l group and The Limiting Factor. 


benchmarking battery packs

Battery Pack Metrics

When designing a battery pack you will always be asked to benchmark it.

Cell Metrics

There are a number of key cell metrics that we expect to see on any cell specification sheet.

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