Product Engineering Processes
Battery Primer
A short battery primer
Handbook of batteries, Linden and Reddy
Short Primer on Batteries
Types
Primary (dry cell): non rechargeable
low power applications
infrequent use
Secondary: rechargeable
high discharge rates
frequent use
Short Primer on Batteries
Selection considerations
Physical characteristics: size, shape weight
Voltage: nominal, maximum, minimum, discharge profile
Load current: rate, constant power, constant resistance, pulsed
Duty cycle: continuous, intermittent, cyclic
Charge/discharge cycle: cycling (float), deep cycle, efficiency of charging
Temperature range: maximum, minimum and nominal
Service life: required operation time
Safety: failure rates, leakage, off-gassing, toxicity, disposal
Environment: vibration, acceleration, orientation
Maintenance: regular upkeep, replacement
Cost: initial, life-cycle cost
Short Primer on Batteries
Cell voltage
Cell voltage
4.5
4
3.5
Voltage (V)
3
2.5
2
1.5
1
0.5
0
Alkaline (p)
Lead-acid (s)
Nickel-Cadmium (s)
Battery type
Nickel-metal
hydride (s)
Lithium-ion (s)
Short Primer on Batteries
Specific energy
Specific energy
160
Specific energy (Wh/kg)
140
120
100
80
60
40
20
0
Alkaline (p)
Lead-acid (s)
Nickel-Cadmium (s)
Battery type
Nickel-metal
hydride (s)
Lithium-ion (s)
Short Primer on Batteries
Energy density
Energy density
450
400
Energy density (Wh/l)
350
300
250
200
150
100
50
0
Alkaline (p)
Lead-acid (s)
Nickel-Cadmium (s)
Battery type
Nickel-metal
hydride (s)
Lithium-ion (s)
Short Primer on Batteries
Self discharge
Shelf life
Shelf life (months@20 Celcius)
60
50
40
30
20
10
0
Alkaline (p)
Lead-acid (s)
Nickel-Cadmium (s) Nickel-metal hydride
(s)
Battery type
Lithium-ion (s)
Short Primer on Batteries
Estimated cycle life
Typical cycle life
Typical cycle life (discharge/charge cycles)
1200
1000
800
600
400
200
0
Alkaline (p)
Lead-acid (s)
Nickel-Cadmium (s)
Battery type
Nickel-metal
hydride (s)
Lithium-ion (s)
Short Primer on Batteries
Temperature range
Operating temperature
80
Temperature (Celcius)
60
40
20
0
Alkaline (p)
Lead-acid (s)
Nickel-Cadmium (s)
-20
-40
-60
Battery type
Nickel-metal
hydride (s)
Lithium-ion (s)
Short Primer on Batteries
Relative cost
Cost
50
45
Relative cost/Wh
40
35
30
25
20
15
10
5
0
Alkaline (p)
Lead-acid (s)
Nickel-Cadmium (s) Nickel-metal hydride
(s)
Battery type
Lithium-ion (s)
Short Primer on Batteries
Voltage and state-of-charge
Short Primer on Batteries
Temperature and energy density
Short Primer on Batteries
Temperature and shelf life
Short Primer on Batteries
Power and discharge rate
Watts/litre
1000
100
10
1
0.2
0.1
1
10
Hours to discharge
100
Alkaline (p )
Lithium ion (s)
Nickel-metal hydride (s)
1000
Nickel-C admium (s)
Short Primer on Batteries
Secondary battery comparison
Lead-acid SLI (starting, lighting, ignition)
advantages
low cost, high availability,
high current, low
temperature, good float
service, maintenance free
Lead-acid traction
lowest cost of deep cycle
systems
Lead-acid stationary
designed specifically for
float charging cycles
maintenance free, long flat
service life, low and high
temperature, operates in
any position
rugged, excellent storage,
high current, low
temperature, operates in
any position
rugged, high energy
density, high current,
operates in any position,
good cycle life
rugged, high energy
density, high specific
energy, operates in any
position, good cycle life, low
self discharge
Lead-acid portable
Nickel-Cadmium (sealed)
Nickel-metal hydride
Lithium ion
disadvantages
Cycle life
low cycle life, shallow
200-700
discharge cycles, low
energy density, poor
charge retention,
hydrogen evolution
low energy density, less 1500
rugged, hydrogen
evolution
hydrogen evolution
Life (years)
4
Cannot be stored
250
discharged, lower cycle
life, difficult for small
batteries
high cost, memory
500
effect, poor for float
service
8
high cost (between
Nickel-Cadmium and
Lithium ion)
5
600
lower current, very high 1000+
cost
6
25
5
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Cycle life and discharge depth (lead-acid)
Short Primer on Batteries
Secondary battery charging
Lead-acid
Nickel-Cadmium (sealed)
Nickel-metal hydride
Lithium ion
charge method
constant current, constant voltage
constant current
constant current, constant voltage
constant current, constant voltage
current rate C(A) charging energy efficiency
0.1
75%
0.3
60%
0.1
60%
0.2
95%
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Constant voltage charging (lead-acid)
Short Primer on Batteries
Constant current charging (lead-acid)