# Custom battery

<p class="callout info">This guide applies to the [easy-pv.co.uk](https://easy-pv.co.uk/) and [easy-pv.ie](https://easy-pv.ie) versions of Easy PV. The information provided here may not be accurate for easy-pv.com.</p>

To add a custom battery in Easy PV navigate to **My Components** &gt; **Batteries** on the left-side menu or **Components** &gt; **Edit Batteries** from the top drop down menu.

You will need the datasheet from the manufacturer, below you will find guidance on how the information in the datasheet corresponds to the values Easy PV asks for.

<p class="callout info">If your custom battery is not showing up in the inverter task, see the 'Rules' section and check the compatibility is correct.</p>

#### **Inputting information from datasheet** 

Below is a list of definitions and potential variations for each value on different manufacturer data sheets:

<div class="pm-table-container with-shadow-observer" data-layout="custom" id="bkmrk-technical-info-varia"><div class="pm-table-wrapper"><table data-layout="default" data-number-column="false" data-table-width="760" data-testid="renderer-table" style="width: 100%;"><colgroup><col style="width: 49.2304%;"></col><col style="width: 50.7696%;"></col></colgroup><tbody><tr><th aria-sort="none" class="ak-renderer-tableHeader-sortable-column__wrapper" colspan="1" rowspan="1">**Technical info**

</th><th aria-sort="none" class="ak-renderer-tableHeader-sortable-column__wrapper" colspan="1" rowspan="1">**Variations**

</th></tr><tr><td colspan="1" rowspan="1">**Battery Capacity:** total battery capacity. Usable capacity may be less if there is a max permitted discharge depth.

</td><td colspan="1" rowspan="1">- Battery module energy
- Battery system capacity

</td></tr><tr><td colspan="1" rowspan="1">**Max Discharge:** maximum depth to which the manufacturer recommends that this battery is discharged. Typically 80 or 90%.

</td><td colspan="1" rowspan="1">- Depth of discharge

</td></tr><tr><td colspan="1" rowspan="1">**Round Trip Efficiency:** percentage of electricity recovered from the battery in a charge-discharge cycle. Around 95% is typical for lithium ion batteries.

</td><td colspan="1" rowspan="1">- Peak round-trip efficiency

</td></tr></tbody></table>

</div></div>The battery will auto-save once all the required fields are completed.

#### **Rules**

Notice you can select a variety of rules for the battery. Some key points:

- It is important you select which inverter groups or which specific inverters the battery is compatible with - either by checking 'Selected inverter groups only' or 'Selected specific inverts only' and selecting from the menu which inverters it is compatible with.
- If your hybrid inverter is an **all-in-one system** and you would like it to appear in one line in the quote then make sure to input the price in the **inverter** and then select 'exclude from shopping cart' in the **battery** rules - this means it will only include and list the cost of the inverter and not the batteries. Note that this will mean additional batteries will not be priced if more than one battery can be included.