The Makita BL1850 5.0ah 18v li-ion battery lithium ion 5 amp LXT uses and optimum charging system that will outperform previous Makita li-ion batteries like the BL1830 BL1840. What are the benefits of the new "Star" Battery The demanding applications you take on every day are also demanding on your cordless tools and batteries. You rely on your tools, so Makita created STAR Protection Computer Controls™. STAR Protection is communication technology that allows the tool and battery to monitor conditions and exchange data in real time to protect against Overloading, Over-Discharging and Over-heating. Look for Makita tools and batteries with the STAR and get these protection features. OVERLOAD PROTECTION High-drain applications require maximum battery power. .