WHAT DOES CAPACITY MEAN?

K (Ah) = I (A) x t (h)

The maximum amount of charge for a fully charged battery to release a stored amount of electricity (ampere-hours/Ah) with a specified current (ampere/A) over a specified time (hours/h). The battery capacities that are specified and shown on the label are the nominal capacities in Ah, which express the maximum current capacity.

When comparing batteries, pay particularly close attention to the capacity!

The capacity (K or C value) of a battery depends on the current with which it’s discharged. The lower the discharge current, i.e. the longer the discharge time, the greater the usable capacity. And vice versa, the greater the discharge current, the less the available capacity. The “K or C” index always indicates the discharge time in hours.

Because the capacity is usually more important than the cold start!

A few facts to briefly take note of: massively increased energy requirements in modern cars, the original batteries that are sometimes designed too tightly, as well as retroactively installed electrical consumers ranging from the auxiliary heating to the sound system.

What does K1, K5, K10, K20 and K100 mean?

K1 Capacity at 1 hour discharge
Main application: USV (Uninterruptible power supply)
K5 Capacity at 5 hours discharge
Main application: Traction drive
K10 Capacity at 10 hours discharge
Main application: motorbikes
K20 Capacity at 20 hours discharge
Main application: SLI (starting lighting ignition)
K100 Capacity at 100 hours discharge
Main application: Solar

Battery capacity: K (Ah) = I (A) x t (h)

I is the discharge current in amperes and t the discharge time in hours

The required battery capacity = sum of all electrical consumers multiplied by the safety factor. With conventional starter batteries, the safety factor (to prevent deep discharges) should normally be 1.7 (1.3 with recombination batteries, i.e. AGM and gel).