We are used to denoting battery capacity in * Amp-hours* (

**). When we look at Tesla Powerwall’s specs sheet, we quite surprisingly**

*Ah**don’t*find the amp-hours specification. What we actually get is this

**“Usable Energy: 13.5 kWh”**. How do we get from this 13.5 kWh to Ah?

Here’s the deal:

How much electricity any battery holds is referred to as *battery capacity*. We are used to looking at 50Ah, 80Ah, 100Ah, 200Ah solar or car batteries and, naturally, we wonder how many Ah is a Tesla Powerwall. First of all, we need to keep in mind that battery capacity can be expressed in these two ways:

**In terms of amp-hours (Ah)**. This is the conventional battery capacity unit we are used to. However, it*doesn’t*really tell us directly how much electricity is in that battery. In order to have a feeling of how much electricity is in the battery, we have to**multiply amp-hours by voltage**(usually 12V battery voltage). The result will be battery capacity in watt-hours (Wh), or, in the case of big batteries like Tesla Powerwall, we can express the result in kilowatt-hours (kWh).**In terms of watt-hours (Wh)**or**kilowatt-hours (kWh)**. This is the direct battery capacity; it*immediately*tells us how much electricity a battery can hold.

The preferable way to report the capacity of bigger batteries is in kWh, and Tesla has done just that. It tells us that Tesla Powerwall+ and Tesla Powerwall 2 hold 13.5 kWh of usable electricity.

Nonetheless, since we have been using amp-hours for most of our batteries, we still want to know how many Ah is a Tesla Powerwall, despite already knowing the kWh capacity. Let’s calculate the Ah from the kWh rating:

## Tesla Powerwall Ah At Standard 12V Battery Voltage

When we see, for example, a 100Ah 12V battery, we know that this battery can deliver an equivalent of 100 amp current at 12V voltage for 1 hour. We can calculate how many kWh of electricity that is like this:

**Battery kWh Capacity (100Ah, 12V) = 100Ah × 12V = 1,200Wh = 1.2 kWh**

With a Tesla Powerwall, we:

*Don’t know*its capacity in terms of Ah or kAh.- We
*do know*its capacity in terms of kWh. Both Tesla Powerwall and Tesla Powerwall have a 13.5 kWh capacity.

If we presume the standard battery voltage applies to Tesla Powerwall (12 volts), we can calculate how many amp-hours is a Tesla Powerwall like this:

**Tesla Powerwall Ah Capacity = 13.5kWh × 1000 / 12V = 1,125 Ah**

As we see, we have multiplied the kWh by 1000 to get Wh and divided by voltage (12V) to get amp-hours. Tesla Powerwall has a **1,125 amp-hours** capacity at 12V battery voltage.

In our photo above, we see two Tesla Powerwalls, and they have double this capacity: 2,250Ah.

Now we can compare Tesla Powerwall capacity to the capacities of common car batteries we are familiar with. Here are some comparisons:

- Tesla Powerwall contains
*more*electricity than. 22 50Ah batteries have a combined capacity of 1,100 Ah, while Tesla Powerall has a 1,125 Ah capacity.*22*50Ah batteries - Tesla Powerwall contains
*more*electricity than. 11 100Ah batteries have a combined capacity of 1,100 Ah, while Tesla Powerall has a 1,125 Ah capacity.*11*100Ah batteries - Tesla Powerwall contains
*more*electricity than. 5 200Ah batteries have a combined capacity of 1,000 Ah, while Tesla Powerall has a 1,125 Ah capacity.*5*200Ah batteries

We hope that this illustrates well how many Ah is a Tesla Powerwall and how it compares to regular 50Ah, 100Ah, and 200Ah batteries.