A previous article explained the purpose of the scheduled charge and discharge function of off grid hybrid inverter. This function can optimize the distribution of power between the utility grid, solar power, and batteries, according to the peak and off peak electricity pricing policies in the user's area, thereby reducing electricity costs. So, does this function affect battery life?
It depends on whether the user uses this function appropriately, setting parameters according to the user manual, and matching the battery type's parameter requirements. Proper settings can extend battery life, while improper settings can accelerate battery life loss.
So, how should you properly set the inverter's parameters? And what parameters should be set improperly? Let's discuss this in detail.
Proper settings can extend battery life. The scheduled charge and discharge function can prevent ineffective battery loss by precisely controlling the charge and discharge periods and thresholds.
Avoid overcharging/overdischarging:
For example, the manual for the Xindun HP PLUS+ off grid hybrid inverter (10KW/12KW) specifies specific safety parameters for different battery types, such as a lead-acid battery over discharge voltage of 42V, a lithium battery over discharge voltage of 36.4-42V, and an overcharge voltage of ≤60V.
When setting the scheduled charge function, you can set the "Battery Boost Charge Voltage" and "Battery Float Charge Voltage" parameters to limit the upper charge limit. For example, setting the float charge voltage to 55.2V for a lead-acid battery can avoid prolonged full charge float charging.
When setting the scheduled discharge function, you can set the "Battery Over Discharge Voltage" and "Discharge Cut off SOC" parameters to limit the lower discharge limit (e.g., SOC ≥ 5%) to avoid deep overdischarge. These inverter parameter settings can reduce battery plate sulfation (lead-acid) or lithium dendrite formation (lithium), thereby extending battery life.
Reduce Frequent Charging and Discharging:
If the timer function is not used, the battery may experience multiple charging and discharging cycles in a short period of time due to fluctuations in solar power generation and changes in load power. For example, on rainy days, when solar power is intermittent, the battery may be repeatedly charged for 20 minutes and discharged for 15 minutes.
Batteries should not be frequently charged and discharged. The inverter's timer function can concentrate the battery's charging and discharging at fixed times, such as fully charging during off peak hours and fully discharging during peak hours (for reference only, subject to actual conditions). This reduces the number of charge and discharge cycles. Properly timed charging and discharging can reduce the rate of cycle consumption.
Maintaining Battery Activity:
If the user does not use the solar power system for an extended period, the battery should be charged at least every three months, as per the user's manual. The timer function can replace manual charging and prevent long term storage of depleted batteries, which can lead to plate sulfation (for lead-acid batteries) and permanent capacity loss (for lithium batteries).
If the user sets parameters outside the manual or uses them improperly, this can directly accelerate battery wear and shorten battery life. Typical examples of improper operation include the following:
Overlapping charge and discharge periods: Setting both "charge" and "discharge" within the same period can cause the battery to "charge and discharge simultaneously," generating excess heat and triggering the "battery overtemperature protection" warning, displaying an error code. Prolonged high temperatures can accelerate electrolyte aging and shorten battery life.
Parameter mismatch with battery type: For example, setting the "overdischarge voltage" for a lithium battery to 42V based on the lead-acid battery standard (the actual overdischarge voltage for lithium batteries should be lower, such as 36.4V for ternary lithium batteries) can cause the battery to "over-discharge." Alternatively, setting the timed charge voltage to 58V (which exceeds the lead-acid battery equalization charge voltage of 56.8V) can cause "overcharging." Both of these improper operations can directly damage the battery and trigger warnings such as "charge overvoltage protection" and "battery undervoltage stop discharge warning." Exceeding the rated discharge load: If the load power exceeds the inverter's rated power (10KW/12KW) for a prolonged period during the scheduled discharge period, or if the starting power of an inductive load (such as a motor) is not reserved 2-3 times the rated power, this will cause a "surge in battery discharge current" (exceeding the maximum discharge current of 200A/220A), triggering the "battery overcurrent protection" warning and displaying an error code. Frequent overcurrent will increase the battery's internal resistance and reduce its capacity.
The scheduled charge and discharge function of the Xindun HP PLUS+off grid hybrid inverter (10KW/12KW) is inherently neutral by design. Its impact on battery life depends entirely on whether the user has set the inverter parameters in compliance. Only by following the inverter's product manual and making targeted settings based on the user's actual usage scenarios can the battery life be effectively extended.
The Xindun HP PLUS+ off grid hybrid inverter (10KW/12KW) features three operating modes: hybrid, off grid, and on grid, enabling the synergistic and complementary integration of solar, utility, and battery power. It supports time based charging and discharging settings with three customizable time periods, taking advantage of peak and valley electricity prices and effectively saving electricity costs. It also supports battery-free operation and supports up to six inverters for single phase or three phase parallel output. It features dual MPPT circuits, can withstand a maximum 500V PV input voltage, and has a PV DC voltage MPPT tracking range of 125V to 425V. It utilizes a high frequency design, pure sine wave output, and achieves inverter conversion efficiency of up to 94%.
For the American market, we also offer an inverter similar to the HP PLUS+ series, the HU. The HU offers the same functionality as the HP PLUS+, but supports both US standard single phase input and output voltages, as well as split phase input and output voltages. For more information, please contact the Xindun team.
