- #1
pchoopanya
- 25
- 0
Hello there,
I am so confused about the term battery specific energy (in Wh/kg) and specific power (in W/kg)
Actually, I know what it means by power and energy, of course P = E/t
But looking at the text, which quotes like "Ni-Cd batteries have high specific energy (than Ld-acid) but the disadtantage is they have low specific power"
and the table says,
Lead-acid 40 Wh/kg 180 W/kg
Nickel-cadmium 50 Wh/kg 120 W/kg
Nickel-metal hydride 70 Wh/kg 200 W/kg
Lithium-ion 130 Wh/kg 430 W/kg
What causes this to happen? How come, for the Ni-Cd which has higher Wh/kg has a lower W/kg compared to Ld-acid?
Isn't power derived from energy divided by time?
Thank you
I am so confused about the term battery specific energy (in Wh/kg) and specific power (in W/kg)
Actually, I know what it means by power and energy, of course P = E/t
But looking at the text, which quotes like "Ni-Cd batteries have high specific energy (than Ld-acid) but the disadtantage is they have low specific power"
and the table says,
Lead-acid 40 Wh/kg 180 W/kg
Nickel-cadmium 50 Wh/kg 120 W/kg
Nickel-metal hydride 70 Wh/kg 200 W/kg
Lithium-ion 130 Wh/kg 430 W/kg
What causes this to happen? How come, for the Ni-Cd which has higher Wh/kg has a lower W/kg compared to Ld-acid?
Isn't power derived from energy divided by time?
Thank you