Lead is a major part of a battery

Many different materials are being used in manufacturing batteries, and of these, lead is definitely the major part.
As the price of lead is fluctuating much – and to prevent having to change our sales prices too often - we have added a lead surcharge to our batteries (appears on a separate line on our invoices)

The surcharge is being regulated each month so that it follows the average lead and exchange rate (USD vs. local currency) based on the previous month.

The Lead Surcharge for July is EURO 22,9,-/KWh

The surcharge is calculated per KWh since this value most accurately reflects the amount of lead in the battery.