2.0Ah vs 4.0Ah
Same fit: these run the same tools
+ Add a battery
Room for one more.
Lowest price we track at UK retailers, updated daily. We may earn a commission
They differ in 5 of 6 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: 43Wh vs 22Wh.
WeightThe 2.0Ah is the lightest at 0.21kg, the 4.0Ah the heaviest at 0.38kg.
PriceThe 2.0Ah is the cheapest of the two today, at £38.99.
Price per Ah4.0Ah £12.25, 2.0Ah £19.50.
Size2.0Ah 87 × 64 × 37mm; 4.0Ah 87 × 64 × 56mm (L × W × H).
Good to know
Same toolsBoth fit every Makita 12V CXT tool.
Same chargersDC10SB and DC10WD charge both. Charge times are in the specs below.
Energy
BL1021B
22Wh
BL1041B
43Wh
Maker figure, or volts × Ah where they don't publish one. Ah and Wh explained ›
Weight
BL1021B
0.21kg
BL1041B
0.38kg
Price per Ah
BL1021B
£19.50
BL1041B
£12.25
Lowest price we track ÷ Ah. Full specs
BL1021BBL1041B
Voltage12V max (10.8V nom)12V max (10.8V nom)
Capacity2.0Ah4.0Ah
Energy22Wh43Wh
Weight0.21kg0.38kg
Energy for its weight103Wh/kg (worked out)114Wh/kg (worked out)
ChemistryLi-ion (cylindrical)Li-ion (cylindrical)
Cell typeNot listedNot listed
Fuel gaugeYesYes
Size (L × W × H)87 × 64 × 37 mm87 × 64 × 56 mm
Charge time, DC10SB30 min1 hr
Charge time, DC10WD1 hr 10 min2 hr 10 min
Lowest price£38.99£49.00
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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