Battery specific energy and power diagram

Do primary batteries have more specific energy than secondary batteries?

Primary batteries have higher specific energy (ability to hold power) than secondary batteries. The below graph compares the typical gravimetric energy densities of lead acid, NiMH, Li-ion, alkaline, and lithium primary batteries. The specific power (ability to deliver power) of rechargeable batteries outperforms primary batteries.

How do you calculate specific energy and power of a battery?

Following this, the corresponding values of specific energy (E * ) and specific power (P * ) are chosen according to and by considering state-of-theart battery characteristics (mentioned in section II-C). The total values for energy and power are found by multiplying corresponding specific values with battery mass.

Are rechargeable batteries better than primary batteries?

The below graph compares the typical gravimetric energy densities of lead acid, NiMH, Li-ion, alkaline, and lithium primary batteries. The specific power (ability to deliver power) of rechargeable batteries outperforms primary batteries. Furthermore, rechargeable batteries are much more resilient under high loads.

What is the theoretical capacity of a battery?

The theoretical capacity of a battery is the quantity of electricity involved in the electro-chemical reaction. It is denoted Q and is given by: Q = xnF (6.12.1) (6.12.1) Q = x n F where x = number of moles of reaction, n = number of electrons transferred per mole of reaction and F = Faraday's constant

What determines the nominal voltage of a battery?

Thus the nominal voltage is determined by the cell chemistry at any given point of time. The actual voltage produce will always be lower than the theoretical voltage due to polarisation and the resistance losses (IR drop) of the battery and is dependent upon the load current and the internal impedance of the cell.

How long does a battery last at a discharge rate?

Energy = ∫ Power ∗ dt ∫ P o w e r ∗ d t . As the battery discharges, it's internal resistance changes, so voltage changes, and so on The power is instantaneous power for a fully charged battery. That rate can not be sustained for a whole hour. Based on the energy you might expect roughly a half hour at that discharge rate.