Makita BL1820B 18V LXT Lithium-Ion 2.0Ah

Makita BL1820B 18V LXT Lithium-Ion 2.0Ah Battery

A lightweight, quick-charging pack for fast-paced work. The BL1820B keeps sub-compact and standard LXT tools nimble, reducing fatigue during repetitive or overhead tasks while minimizing downtime between swaps.

Key specs

• Capacity: 2.0Ah (approximately 36 Wh)
• Typical charge time: about 25 minutes on a Makita Rapid Optimum Charger
• Electronics: Star Protection for overload, over-discharge, and overheating
• Indicator: onboard LED fuel gauge
• Compatibility: over 275 Makita 18V LXT tools (not for 12V CXT or 40V XGT)

Best for

• Assembly, trim work, cabinet installs, and punch-list tasks
• Impact drivers, drill/drivers, oscillating tools, and sub-compact LXT tools
• Short, frequent tasks where fast charging beats maximum runtime

Consider a higher Ah pack if

• You run high-draw tools for extended periods (circular saws, grinders, paddle SDS)
• You need fewer battery swaps on full-day jobs
• You frequently use 18V X2 (36V) tools that require two batteries

Runtime examples

Runtime depends on tool load. The 2.0Ah pack stores about 36 Wh. Estimate minutes as 36 ÷ watts × 60.

• Light work (≈40 W, e.g., fastening, light drilling): about 50–55 minutes
• Moderate work (≈80 W, e.g., oscillating tools, small hole saws): about 25–30 minutes
• Heavy work (≈120–150 W, e.g., circular saw rip cuts): about 14–18 minutes

Actual results vary with bit sharpness, material, temperature, and tool efficiency.

Pros

• Very light, reduces arm and shoulder fatigue
• Fast recharge keeps work moving with one or two packs
• Fuel gauge simplifies pack management

Trade-offs

• Shorter runtime than 3.0–6.0Ah batteries
• May hit thermal or voltage cutoffs sooner on sustained heavy loads

Charging and care

• Let the pack cool to room temperature before charging, especially after heavy use
• For fastest turnaround, use a Makita Rapid Optimum Charger
• Avoid deep discharges; swap packs around 10–20% remaining to reduce wear
• Store long-term around 40–60% charge in a cool, dry place; avoid heat and moisture
• Do not use or charge if the pack is damaged or swollen

Compatibility notes

• Fits all Makita 18V LXT tools and chargers; not compatible with 12V CXT or 40V XGT systems
• For 18V X2 (36V) tools, you need two batteries; the tool stops when either pack is depleted, so two 2.0Ah packs will limit runtime

Alternatives within LXT

• 3.0Ah: about 1.5× the runtime with modest weight increase; a balanced upgrade
• 5.0Ah: about 2.5× the runtime; good for general carpentry and longer sessions
• 6.0Ah: about 3× the runtime; best for high-draw tools and all-day work

FAQ

• How long does it take to charge?

  About 25 minutes on a Makita Rapid Optimum Charger. Other compatible chargers may be slower.

• Will it run high-draw tools like circular saws?

  Yes, but expect shorter runtime and earlier thermal/voltage cutoffs under continuous heavy load. A 5.0Ah or 6.0Ah pack is a better match for sustained cutting.

• Can I mix a 2.0Ah with a 5.0Ah on an 18V X2 tool?

  Not recommended. The tool stops when the first pack empties, so a smaller pack will limit runtime. Use two packs of the same capacity and similar age for best results.

• Does it have memory effect?

  No. Lithium-ion batteries have no memory; partial charges are fine.

• How should I store it long-term?

  Store at roughly half charge in a cool, dry place. Check and top up every few months.