4BS-Tetra Lead Sulfate “AddBATT Tetra L2 “for positive plate
4BS (Tetra Basic Lead Sulfate, PbSO4.4PbO)come from PbO (Oxide of Orthorhombic Crystal Structure), it will become Alpha–PbO2 through a formation process which is better in life cycle.
Generally,a surface of positive grid in formed plate has a structure of Alpha–PbO2 and a surface of positive plate in formed plate has a structure of Beta–PbO2, because Alpha-PbO2 formed at an alkalinity circumstance and Beta-PbO2 formed at an acidity circumstance.
Specially, an oxide from Ball Mill has 100% of Tetragonal Crystal Structure’s PbO, it will become 3BS (Tri Basic Lead Sulfate, PbSO4. 3PbO) through Paste Mixing / Curing Process, and then it will become a structure of Beta-PbO2 through a formation process. Beta-PbO2 in positive plate has better performance than Alpha-PbO2 in positive plate.
But, Beta-PbO2 has lower life than Alpha PbO2 in positive plate. It needs 4BS as a seed of Alpha-PbO2 who use an oxide from Ball Mill Oxide Machine to make Alpha-PbO2 what has better life in positive plate. Barton Oxide has 5~30% of Orthorhombic Crystal Structure’s PbO according to an operation parameters, Orthorhombic-PbO will become 4BS through Paste Mixing / Curing (Hydroset) /Drying process.
[2-1]. To form Alpha–PbO2 in formed positive plate, 4BS need in unformed plate;
Generally, to create Alpha-PbO2 in positive plate :
a) High wet paste density in paste mixing.
– If a density is too high, it is not good for high rate discharge because of low porosity.
b) Low specific gravity acid for charging.
– If a specific gravity is too low, PbSO4 in unformed plate will dissolve easily in acid before charging process. An then, it will create a short circuit ( Dendrite ) due to hydration ( PbSO4 accumulate in a separator ) at separator. It will happen when a soaking time is too long at formation process.
c) Low temperature control at charging process.
-If a temperature is too low, a shedding will happen because cohesion of active material is lower due to an excessive Alpha–PbO2.
d) High temperature in a curing process.
– If a temperature is too high, an excessive 4BS will interrupt an initial performance.
[2-2]. When 4BS add in paste mixing process as a seed, 4BS will spread evenly in paste. Alpha Pb O2 will formed at a surface of grid, in the active material and a surface of plate through formation process.
[2-3]. A weight percentage of 4BS is 1~2% of oxide weight.
[2-4]. 4BS will has additive affect in curing time.