WECO 5K3-XP-EMEA
7
System Design
System Design is the process of defining the architecture, components, modules, interfaces and load data for a
system to satisfy specified requirements.
For a solar energy system, these components are the PV modules, inverter/charge controller & batteries, as
well as the different interfaces of those components.
Battery Operation
There are several factors that affect the operation of the battery that could impact its ability to deliver capacity
and life expectancy.
Storage
Battery Module shall be stored in original packaging, in a clean, level, dry, cool location indoors.
Recommended storage temperature is 77°F / 25°C
The battery can be stored in the range of -4°F to +113°F / -20°C to +45°C but it requires an inspection* and recharge**
every three months (max charging current is 0.1C to recover from low voltage status during the storage period ).
Max SoC storage is 50%.
*Inspection parameters
–
identify the State of Charge (SOC), look for any alarms and address accordingly, look for physical
damage to the Battery Module. **Charge at 0.1C and not more than 50% SOC. If shipped by sea, you must refer to the
UN38.3 standard, if by road, refer to the local codes.
Temperature
Many chemical reactions are affected by temperature, and this is true of the reaction that occurs in a storage battery.
The chemical reaction of a Li-Ion is slowed down by a lowering of the electrolyte temperature that results in less capacity.
A battery that will deliver 100% of rated capacity at 77°F /25°C will only deliver approximately 75% of rated capacity at +50°F
/ +10°C
At temperatures down to +19.4°F /+7°C the charge current may be limited to 0.1C depending on other factors, however at
temperatures below +19.4°F /-7°C charging is restricted by the BMS.
As part of the Performance Warranty, Charge and Discharge shall be in the range +68°F to +77°F +20°C to +25°C Any usage
outside this range is not covered by Performance Warranty.
Depth of Discharge (DoD)
Depth of discharge is a function of design. The deeper the discharge per cycle, the shorter the life of the
battery. A cycle is a discharge and its subsequent recharge regardless of depth of discharge, it consider the
energy IN and OUT
Lower is the DOD value higher is the battery longevity and the capacity retention over the time.
C-Rate
Value of the Current used to charge and discharge the battery is expressed in C ( 1C = 100A, 0,1C= 10A in case
of the 5K3 100Ah battery)
Charging ( and discharging)
Most battery capacity/life issues can be traced to improper charging. Improper charging settings may lead to an
overcharging or undercharging condition, any wrong charging process will affect the life of the battery or its
ability to retain energy
Lower is the C-Rate of the charging/discharging process and more the battery will benefits on the long term
performances
Manufacturing Warranty
Although the BMS of the battery allows a wide range of use, both in terms of temperature and charging
currents, this should not be construed as an implicit authorization to use the battery at these levels.
For the purposes of the Performance Warranty, it is mandatory that the battery is used within the range of
temperature and charge/discharge current, and Depth of Discharge indicated in the Performance Warranty.
See Limited Warranty Document
Performances Warranties
when
It is an additional Warranty and only apply to batteries connected via BMS line to an approved inverter, the working
parameter of the battery must remain within the performance warranty terms
Any other use, even if permitted by the BMS ranges, is not covered by the Performance Warranty
See Limited Warranty Document