Week 1 Understanding Different Battery Chemistry

LITHIUM COBALT OXIDE (LiCoO2):

Developed by Prof. Good enough IN 1980’s

• Cathode-Cobalt Oxide
• Anode – Graphite

Benefits: High specific energy, stable capacity.

Drawbacks – Low thermal stability, Limited specific power, High cost of cobalt and even mining is dangerous, Only found in Congo.

Fig: LiCoO₂ SEM image

TECHNICAL SPECIFICATION:

VOLTAGE	3.6V NOMINAL,3.0V-4.2 V
SPECIFIC ENERGY	150-200 WH/KG
CHG RATE	0.7-1C
DCHG RATE	1C
CYCLE LIFE	500-1000
THERMAL RUNAWAY	>150 CELCIUS

Applications – Laptops, mobile phones and most consumer electronics.

LITHIUM MANGANESE OXIDE (LiMn2O4)

Cathode structure-Spinal, which improves ion flow on electrode which results in lower internal resistance. Cell can handle high current while charge/discharge and has high thermal stability.

TECHNICAL SPECIFICATION:

VOLTAGE	3.7V NOMINAL,3.0V-4.2 V
SPECIFIC ENERGY	100-150WH/KG
CHG RATE	0.7-1C,3C MAX
DCHG RATE	1C,10C,30C Pulse
CYCLE LIFE	300-700
THERMAL RUNAWAY	>250 CELCIUS

Applications: Power tools, Medical devices.

Lithium Nickel Manganese cobalt oxide (LiNiMnCoO2):

Used in TESLA Electric vehicles, MODEL 3.They have significantly reduced the cobalt content and increased the Ni content and still maintaining the thermal stability.

The ratio of Ni: Mn: Co was 8:1:1, because as a result the gross weight of MODEL 3 is on Par with the gasoline powered counterpart.

TECHNICAL SPECIFICATION:

VOLTAGE	3.7V NOMINAL,3.0V-4.2 V
SPECIFIC ENERGY	150-220WH/KG
CHG RATE	0.7-1C,
DCHG RATE	1C,2C rapid
CYCLE LIFE	1000-2000
THERMAL RUNAWAY	>210CELCIUS

Application: E bikes, Medical devices, EV ‘S, Industrial robots.

Additives are added to increase the charge rate or the ratio of Ni:Mn:Co is changed.

Lithium Ferro Phosphate (LiFePO4):

Cathode-Olivine structure, Benefits of structure are as follows

• High current rating
• Long cycle life
• Good thermal stability
• More safe to operate than LiCoO₂

Drawback:

Low nominal voltage, low specific energy.

Fig: LFP SEM images

TECHNICAL SPECIFICATION:

VOLTAGE	3.3V NOMINAL,2.5V-3.65 V
SPECIFIC ENERGY	90-120WH/KG
CHG RATE	1C
DCHG RATE	1C,25C rapid,2.5 V cut off
CYCLE LIFE	1000-2000
THERMAL RUNAWAY	>270CELCIUS

Application: Portable and stationary applications, high load current applications and energy storage.

Lithium Titanate (Li₄Ti₅O₁₂)

Anode: Lithium Titanate

Cathode - Lithium manganese oxide or NMC.

Key advantages:

• Low risk of thermal runaway
• Impressive life cycle
• High charge/discharge rates

Drawback:

Low nominal voltage, low specific energy.

TECHNICAL SPECIFICATION:

VOLTAGE	2.4V NOMINAL,2.5V-3.65 V
SPECIFIC ENERGY	50-80WH/KG
CHG RATE	1C,5C MAX
DCHG RATE	10C,30C PULSE, 1.8 V cut off
CYCLE LIFE	3000-7000
THERMAL RUNAWAY	NA

APPLICATIONS:

UPS, Electric power train, solar powered street light etc.