Types of battery charging.

1. Top up:

• it is charging, the purpose of which is to replenish the electric charge in the battery,

• all three charging methods can be used here:

■ at a constant voltage value of from 2,35 do 2,45 V/cell,

■ at constant current:

— single-stage — charging current I_order = 0,1 Q₂₀,

— two-stage — charging current in the first phase I_order = 0,1 Q₂₀ and in the second with value I_order = 0,05 Q₂₀,

■ at constant current and voltage:

— in the first phase — with the charging current I_order = 0,1 Q₂₀,

— in the second phase — at the charging voltage U_order = 2,4 do 2,45 V/cell.

2. Boost:

• this is an accelerated battery recharge used only in emergency cases, to continue driving; Supercharging allows you to bring a large amount of charge to the battery in a very short time, e.g. for approx 0,5 h can be supplied this way around 50% electrical charge needed to fully charge the battery:

• recharge is usually performed:

■ two-stage with constant charging current:

— in the first phase (until the gassing voltage occurs) current with a maximum value of I_order = 0,8 Q₂₀ (e.g. for a battery with a capacity of Q₂₀ = 34 A h this current will be I_order = 27,2 A),

— in the second phase (until fully charged) with a current of I_order = 0,1 Q₂₀,

■ one-stage with constant charging voltage U_order = 2,4 do 2,45 V/cell; in the initial charging period for a battery charged in 35 do 40% the charging current at this voltage can reach even 0,9 Q₂₀, then it will begin to decrease and reach approximately the following average values:

— 30 A for batteries charged in 50%,

— 15 A for batteries charged in 75%,

— 2 And for batteries almost fully charged.

3. Equalizing charge:

• is only used to equalize the state of charge of all battery cells; in this type of charging, a charge is applied to the battery after it has already shown signs of being fully charged - this is known as. overload;

• they are usually carried out in one stage at a constant value of the charging current I_order = 0,05 Q₂₀, delivering an electric charge to the battery 2 do 3 Q₂₀[A· h];

• overcharging is harmful to the battery, but in cases of necessity, they are used for up to three days, but with a current not greater than I_order = 0,05 Q₂₀.

4. Desulphation charging:

• carried out after finding the sulphation of the battery plates (the causes and symptoms of sulfation have been described previously);

• in the case of deep sulphation, desulphation charging may not give any effect or only give short-term effects; all right, but sometimes only short-term effects are achieved by recharging the battery several times (3 do 4 cycles) with each time the electrolyte is replaced after charging with distilled water; the last charging cycle is carried out, filling the battery with a density electrolyte 1,26 g/cm³ and loading by any method (however, desulphation charging current is most commonly used);

• usually carried out in one step at a constant value of the current I_order = 0,02 do 0,05 Q₂₀ (until fully charged); is recommended after approx 12 h charging done 2 h break; after charging is completed, its effects should be checked, assessing the state of charge of the battery; if it is at least 70%, the above-mentioned top-up is carried out, if not, the desulphation charge should be repeated and the electrolyte replaced several times.

Summary of typical values ​​of charging currents for selected batteries of domestic production

Battery type	Capacity electric Q20 [A ·h]	charging currents [A]
		0,02Q20	0,05Q20	0,01Q20	0,08Q20
6SC34, 6SC34F	34	0,68	1,7	3,4	27,2
6SC45, 6SC45F, 12M2	45	0,9	2,25	4,5	36,0
6SE60, 6SE60MN	60	1,2	3,0	6,0	48,0