Installation Guide

Itron recommends you conduct open circuit voltage audits every six months on batteries stored
at or near 25°C (77°F). Recharge batteries when OCV readings approach 6 volts (2.00 volts per
cell). Increase OCV audits if storage temperatures are significantly higher than 25°C (77°F)—
even for short durations.
It is important to recognize the self-discharge rate of the battery is non-linear. The rate of self-
discharge changes as the battery's state of charge (SOC) changes. The time taken for a battery
to discharge from a 100% SOC to 90% SOC is different from the time it takes to self-discharge
from a 20% SOC to a 10% SOC.
State of Charge
The state of charge (SOC) of the battery can be approximated by using the curve shown in the
following chart. This curve is accurate to within 20% of the true SOC of the cell under
consideration, if it has not been charged or discharged within the past 24 hours. The curve is
accurate to within 5% if the cell has not seen any activity, charge or discharge, for the past five
days.
23 June 2020 TDC-0971-012 Itron, Inc. Page 70 of 134
CCU 100 and Repeater 100 Installation Guide 5 Battery Care and Maintenance