Preparation for commissioning of new storage batteries. Selection and restoration of battery cells for the purpose of verification of their further use.
Initial conditions:
- New 2V battery cells are jelly-like one batch and one factory of the manufacturer. They may be kept at rest for varying periods of time.
- The battery cells that were in service can be different manufacturers, different production times but necessarily of the same denomination.
- In the charging-discharging group either only new or only was in service.
Dynamics of the restoration service process.
Preventive discharge is carried out with the use of intelligent automatic charging and discharging devices where the algorithm is based on V. Dankov method. After the prophylactic discharge they withstand a technological 2-hour pause. Read and write an electromotive force value on the pole terminals of each battery cell. According to this data charging groups are formed from battery cells. In each group from the “+” side of the output put rechargable cell which value E1V is the largest the rest in order of reducing the index E. Due to the fact that a greater value of E may occur due to sulfating battery cell the difference in E values among battery cells is limited to no more than Emax – Emin <= 0.02V.
Restoration charge is carried out using intelligent automatic charging and discharging devices where V. Dankov technique is used as the basis for the work algorithm. When charging the current strength of the power indicators should be not less than Izmax >= 0.08 Cnom (where Cnom is the rated capacity of the serviced storage battery)
After the recovery charge is carried out, the battery cells under control are kept in peace for 2 to 3 hours. They are then tested for selective selection for possible use in a single storage battery. For this purpose the test battery cells are connected in series to 12V test groups and are subjected to a load current of In = 0.1+/-0.05 Cnom. In the process of this read and write the value of discharge voltage on the pole terminals of each battery cell after 2 minutes and 10 minutes from the beginning of the test discharge (Ur2 and Ur10). The data obtained is used to determine the quality of each controlled battery cell.
qi = Ur2 – 2(Ur2-Ur10),V
The best battery cell is the one where the value of qi is greater and with equal values of qi the best battery cell is the one where the value of Ur2-Ur10 V is less.
If as a result of check it will be found out among new battery cell with index qi < 1,9V and among battery cell in service with index qi < 1,82V for such battery cell it is necessary to carry out additional cycles of restoration service with use of remote control where in the basis of algorithm of work V. Dankov’s technique is applied.
For admission to further use of both new battery cell and battery cell in service must be complied with requirements:
For new ones (after their forming charge):
Ci >= 0.95 Cnom
QЗ1 >= 1,25 Сnom
Q3k >= 2,5 Сnom
Q3k <= 3,0 Сnom
For storage battery in service:
Ci >= 0,8 Cnom
Q3 >= 0,6 Cnom
Q3k >= 1,4 Сnom
Q3k <= 1,85 Сnom
Q3k >= 1,3 Q31
where:
Ci – the value of nominal capacity determined by the dependence of
Ci = (1,4*Q3 + 0,66*Q3k) / 2+/- Cnom — (for storage battery in service)
Ci = (0,85*Q3 + 0,66*Q3k) / 2+/- Cnom — (for new storage battery)
Q3 – the amount of electricity reported by the controlled storage battery from the beginning of charging to the achievement of charging voltage at its pole terminals Uz = 13.8 V
Q3k – amount of electricity reported to the storage battery for the entire charging process.
If at least one of the requirements of the system is not met the controlled storage battery is excluded from operation.
After the above mentioned tests the battery cells in the storage battery may be allowed to be used with a reserve of service life reliability:
– for new storage battery – at least 8 years.
– for battery cell in service – at least 4 years
At the same time a repeat of the recovery cycle can be recommended every 1.5-2 years then the new storage batteries will be able to operate reliably for up to 12 years and the storage batteries in service for up to 6 years.
The storage battery is installed on the object of its use and connected to a permanent power source (solar panels) through the intelligent automatic charging and discharging devices where the basis of algorithm is the method of V. Dankov.
Constant Charging Mode
– until the voltage is reached at the pole terminals of the intelligent automatic charging and discharging devices Uz = E,V the process occurs without any restrictions
– After reaching Uz >= E and before reaching Umax (the upper limit of voltage in recharging mode) every 100 seconds increase the value of Uz by 5 millivolts at the rate of one 2V battery cell.
Umax depends on the ambient temperature which can vary from +10 to +55 °C.
When Uz = Umax is reached, you will automatically switch to pre-discharge mode. In this mode the upper limit of Uz = 2.4V, based on each one of the 2V battery cell of their storage battery.
When Umax is reached turn on the timer where Tt = 6 hours. At this time monitoring the storage battery status every 30 minutes on conditions :
– tt = 6 hours
— Iк >= In
— Uк <= Un
where In is the current at the beginning, Ik is the current at the end of the controlled 30 minute, Un is the charging voltage at the beginning, Uk is the charging voltage at the end of the controlled 30 minute.
If these conditions are met the transition to constant charge mode will be automatically performed to reduce the Uz value by 20 millivolts every 100 seconds for one 2V battery cell in storage battery.
When you reach Uz = Umax charge stabilizing this level of Uz.
Special conditions.
1. If the Iz level exceeds 0.15A of the maximum standard set for this object every 10 milliseconds reduce the Uz level by 40 millivolts based on 2V battery cell in storage battery. In case such position takes place within more than 30 milliseconds – declare a “short-circuit” type accident.
2 At decrease of charge voltage at the pole terminals of intelligent automatic charging and discharging devices to the level of Uz <= 1,6V at the rate of each battery cell in the storage battery – take the device to the position “END Mode”.