They differ in 3 of 4 areas
Same tools, so this is about size, weight and cost. No overall winner: pick the size that suits the job.
EnergyThe 5.0Ah stores 67% more than the 3.0Ah: 90Wh vs 54Wh.
WeightThe 3.0Ah is the lightest at 0.38kg, the 4.0Ah the heaviest at 0.56kg.
Size3.0Ah 116 × 76 × 49mm; 4.0Ah 134 × 83 × 54mm; 5.0Ah 97 × 76 × 71mm (L × W × H).
Good to know
Same toolsAll three fit every HiKOKI 18V tool.
Same chargersUC36YSL2 and UC18YKSL charge all three. Charge times are in the specs below.
Energy
BSL1830C
54Wh
BSL1840M
72Wh
BSL1850C
90Wh
Maker figure, or volts × Ah where they don't publish one. Ah and Wh explained ›
Weight
BSL1830C
0.38kg
BSL1840M
0.56kg
BSL1850C
0.55kg
Full specs
BSL1830CBSL1840MBSL1850C
Voltage18V18V18V
Capacity3.0Ah4.0Ah5.0Ah
Energy54Wh72Wh90Wh
Weight0.38kg0.56kg0.55kg
Energy for its weight142Wh/kg (worked out)129Wh/kg (worked out)164Wh/kg (worked out)
ChemistryLi-ion (cylindrical)Li-ion (cylindrical)Li-ion (cylindrical)
Cell typeNot listed21700 cylindricalNot listed
Fuel gaugeNot listedYesNot listed
Size (L × W × H)116 × 76 × 49 mm134 × 83 × 54 mm97 × 76 × 71 mm
Charge time, UC36YSL230 min40 min25 min
Charge time, UC18YKSL1 hr 30 min2 hr2 hr 30 min
Lowest priceNo retailer price yetNo 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.
Battery guides
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