2.0Ah vs 3.0Ah vs 4.0Ah
Same fit: these run the same tools
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They differ in 4 of 4 areas
Same tools, so this is about size, weight and cost. No overall winner: pick the size that suits the job.
EnergyThe 4.0Ah stores 100% more than the 2.0Ah: 72Wh vs 36Wh.
WeightThe 2.0Ah is the lightest at 0.35kg, the 4.0Ah the heaviest at 0.61kg.
Size2.0Ah 113 × 73 × 39mm; 3.0Ah 115 × 74 × 56mm; 4.0Ah 121 × 80 × 51mm (L × W × H).
Chemistry2.0Ah: Li-ion (cylindrical); 3.0Ah: Li-ion; 4.0Ah: Li-ion (cylindrical).
Good to know
Same toolsAll three fit every Bosch 18V Professional tool.
Energy
GBA18V-20
36Wh
GBA18V-30
54Wh
EXBA18V-40
72Wh
Maker figure, or volts × Ah where they don't publish one. Ah and Wh explained ›
Weight
GBA18V-20
0.35kg
GBA18V-30
0.6kg
EXBA18V-40
0.61kg
Full specs
GBA18V-20GBA18V-30EXBA18V-40
Voltage18V18V18V
Capacity2.0Ah3.0Ah4.0Ah
Energy36Wh54Wh (worked out)72Wh
Weight0.35kg0.6kg0.61kg
Energy for its weight103Wh/kg (worked out)90Wh/kg (worked out)119Wh/kg (worked out)
ChemistryLi-ion (cylindrical)Li-ionLi-ion (cylindrical)
Cell typeNot listedNot listedNot listed
Fuel gaugeYesNot listedYes
Size (L × W × H)113 × 73 × 39 mm115 × 74 × 56 mm121 × 80 × 51 mm
Lowest price£56.99No retailer price yetNo retailer price yet
Specs from each maker's own documentation. "Not listed" means the maker doesn't publish it or we haven't found it yet; it never counts as a difference.
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