What is the difference between specific power and energy density?

Specific Power (W/kg) – The maximum available power per unit mass. Specific power is a characteristic of the battery chemistry and packaging. It determines the battery weight required to achieve a given performance target. Energy Density (Wh/L) – The nominal battery energy per unit volume, sometimes referred to as the volumetric energy density.

What does energy mean in a battery?

Energy or Nominal Energy (Wh (for a specific C-rate)) – The “energy capacity” of the battery, the total Watt-hours available when the battery is discharged at a certain discharge current (specified as a C-rate) from 100 percent state-of-charge to the cut-off voltage.

What is a rate constant in chemistry?

These are all included in the so-called rate constant - which is only actually constant if all you are changing is the concentration of the reactants. If you change the temperature or the catalyst, for example, the rate constant changes. This is shown mathematically in the Arrhenius equation. Starting with the easy ones . . .

What is the value of the gas constant R?

The value of the gas constant, R, is 8.31 J K -1 mol -1. You can see that the fraction of the molecules able to react has almost doubled by increasing the temperature by 10°C. That causes the rate of reaction to almost double. This is the value in the rule-of-thumb often used in simple rate of reaction work.

What is specific energy in a car battery?

Specific Energy (Wh/kg) – The nominal battery energy per unit mass, sometimes referred to as the gravimetric energy density. Specific energy is a characteristic of the battery chemistry and packaging. Along with the energy consumption of the vehicle, it determines the battery weight required to achieve a given electric range.

What does the rate equation show?

The rate equation shows the effect of changing the concentrations of the reactants on the rate of the reaction. What about all the other things (like temperature and catalysts, for example) which also change rates of reaction? Where do these fit into this equation?