Powerwall – Rechargeable Lithium Battery for Home Use

What is Powerwall?

The rechargeable lithium battery by Tesla Motors for household use is Tesla Powerwall. It can store electricity for domestic use, backup power and load shifting etc. it is stationary energy storage for off the grid use.


What the Tesla batteries are made of?

The battery is containing 7,104 lithium ion battery cells. Cathode of the cell consists of combination of different elements including lithium. The S-model battery is according to the NCA formulation with a ratio of approx.:  80% nickel, 15% cobalt and 5% aluminum.

Originally the company launch the Powerwall in 2015 with an output power of 2 kW steady and 3.3 kW maximum. At the time of launch, the company introduce two models of the Power Wall . The first was for the backup applications and second for daily cycle applications with capacity of 10kWh and 7kWh respectively. panasonic-tesla-pack-by-theron-trowbridge

Powerwall 2:

This new model of the Powerwall is launched on October 2016. It is a blend of two technologies, the solar panel by SolarCity and Powerwall by Tesla Motors. This Powerwall is intended to work with solar panel roofs.


At the start there was a 6.4 kWh capacity Powerwall for daily cycle application. To enlarge the capacity you can join multiple Powerwalls for greater energy needs. The 10 kWh capacity model for backup power was discontinued in March 2016 because now the 6.4 kWh model can be used for backup power.


Powerpack is a large unit for commercial or industrial use with 100 kWh and 210 kWh storage. To meet the diversity of industrial energy needs, Powerpack is extremely scalable, says Musk, CEO at Tesla Motors.  The Powerpack 2 has a storage capacity of 200 kWh.


The Powerwall is augmented for daily cycling. The 7 kWh battery is build with nickel-manganese-cobalt and can complete 5,000 cycles before being expire. When the product is new the Tesla Powerwall has 92% efficiency if charged with a 400-450 V voltage source at 2 kWh keeping temp at 25 degree. However the efficiency of the product becomes low if one keeps the unit  above or below 25 o and charging or discharging rate is above 2 kWh.

Comparative Products in the market:

A California energy technology company” Enphase Energy” has designed lithium iron enphase-battery-storage phosphate battery as complete home energy solution starting this winter (2016). Enphase’s batteries are more efficient than Powerwalls with a 96% round trip efficiency as compared with 92% of the Tesla Powerwall. Enphase’s battery includes an inverter inside the case and is compatible with all solar systems or without solar system. Lithium iron phosphate batteries are the best and utmost stable among different lithium batteries.

Demo Video:



Leave a Reply