Functionalized Nano-porous Silicon Surfaces for Energy …
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V = E − IR
(3)
where E is the fixed voltage, I is current flowing in the circuit and R is the internal
resistance.
3.1.2 Battery Capacity
The energy stored in a battery called the battery capacity and measured either in
ampere-hours (Ahr) or Watt-hours (Wh), kilowatt-hours (kWh).
3.1.3 Energy Stored
The energy stored in the battery depends on the charge stored and its voltage.
Energy in Whr = V × Ahr.
3.1.4 Specific Energy
Specific energy is the amount of electrical energy stored per unit mass and has units
of Wh kg
−1 .
3.1.5 Energy Density
Energy density is the amount of electrical energy stored in a given system per unit
volume. It normally has units of Wh m
−3 .
3.1.6 Specific Power
Specific power is the amount of power obtained per kilogram of battery. It is a highly
variable and rather anomalous quantity, since the power given out by the battery
depends more on the load connected to it than the battery itself.
3.1.7 Power Density
Power density is the maximum power per unit volume and measures how quickly
the battery can deliver energy. Its units are W/kg or W/m
3 .
Reasonable price, high energy density, fast charging and discharging capability,
safety, and good durability are the key characteristics of an optimal battery. The
energy density of a battery can be varied by three factors: (1) by having a large
chemical potential difference between the two electrodes; (2) by making the volume
387
V = E − IR
(3)
where E is the fixed voltage, I is current flowing in the circuit and R is the internal
resistance.
3.1.2 Battery Capacity
The energy stored in a battery called the battery capacity and measured either in
ampere-hours (Ahr) or Watt-hours (Wh), kilowatt-hours (kWh).
3.1.3 Energy Stored
The energy stored in the battery depends on the charge stored and its voltage.
Energy in Whr = V × Ahr.
3.1.4 Specific Energy
Specific energy is the amount of electrical energy stored per unit mass and has units
of Wh kg
−1 .
3.1.5 Energy Density
Energy density is the amount of electrical energy stored in a given system per unit
volume. It normally has units of Wh m
−3 .
3.1.6 Specific Power
Specific power is the amount of power obtained per kilogram of battery. It is a highly
variable and rather anomalous quantity, since the power given out by the battery
depends more on the load connected to it than the battery itself.
3.1.7 Power Density
Power density is the maximum power per unit volume and measures how quickly
the battery can deliver energy. Its units are W/kg or W/m
3 .
Reasonable price, high energy density, fast charging and discharging capability,
safety, and good durability are the key characteristics of an optimal battery. The
energy density of a battery can be varied by three factors: (1) by having a large
chemical potential difference between the two electrodes; (2) by making the volume