Background Information; Peukert's Exponent - Victron energy BMV 600 Manuel

If using a shunt other than the one supplied with the BMV, the following
additional steps are required:
1. Unscrew the PCB from the supplied shunt.
2. Mount the PCB on the new shunt, ensuring that there is good
electrical contact between the PCB and the shunt.
3. Set the correct values for the ShA, and ShV parameters (see
chapter 2.5).
4. Connect the shunt to both the positive and negative of the
battery as described in the installation guide, but do not connect
anything to the load side of the shunt.
5. Issue the zero command (see chapter 2.5).
6. Disconnect the negative battery connection from the shunt.
7. Connect the load to the shunt.
8. Reconnect the battery negative to the shunt.

2.3 Background information

When your BMV is installed it is time to adjust the battery monitor to your
battery system. But before discussing the functions in the setup menu, four
important items must be explained first. It is important that as a user of the
BMV you have some insight into these four items. The actual setup menu
functions are explained in chapter 2.5 – Function overview.
2.3.1 Charge Efficiency Factor (CEF)
During battery charging, not all of the energy transferred into the battery is
available when the battery is being discharged. The charge efficiency of a
brand new battery is approximately 90%. This means that 10Ah must be
transferred to the battery to get 9Ah actually stored in the battery. This
efficiency figure is called the Charge-Efficiency-Factor (CEF) and will
decrease with battery age. The BMV can automatically calculate the CEF of
the battery.

2.3.2 Peukert's exponent

As mentioned in chapter 1.3, the Peukert efficiency describes how, when
you discharge a battery faster than the 20hr rating, its Ah capacity
decreases. The amount of battery capacity reduction is called the 'Peukert
exponent' and can be adjusted from 1.00 to 1.50. The higher the Peukert
exponent the faster the battery size shrinks with increasing discharge rate.
An ideal (theoretical) battery has a Peukert Exponent of 1.00 and has a
fixed capacity; regardless of the size of the discharge current. Of course
such batteries do not exist, and a setting of 1.00 in the BMV is only
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