4S 14.8V / 16.8V 20A Li-Ion BMS with Balance 18650 Lithium Battery Protection Board Overcharge, Over-Discharge, Short Circuit Safety

Building a DIY battery pack without protection is a fire hazard waiting to happen — the 4S 14.8V/16.8V 20A Li-Ion BMS gives your 18650 lithium battery pack the intelligent safeguarding it deserves, all in one compact board.

This Battery Management System (BMS) is engineered for 4-series Li-ion and Li-polymer packs, delivering four-layer protection: overcharge cutoff at 4.25V per cell, over-discharge cutoff at 2.5V per cell, overcurrent protection at 20A peak, and instant short-circuit shutdown. The built-in cell balancing circuit keeps all four cells equalised during charging, preventing capacity drift and extending the overall lifespan of your battery pack significantly. It supports a charging voltage of 17–18V with up to 10A charging current, and handles 15A continuous discharge with 20A peak — more than enough for power-hungry applications.

Whether you are building a solar street light, a portable power station, a DIY power bank, or a cordless power tool battery, this BMS fits right in. Its wide operating temperature range of -20°C to 80°C makes it equally reliable in Rajasthan summers and Himalayan winters. The compact PCB design integrates easily into custom enclosures, and the clearly labelled B-, C-, and P- pads simplify wiring even for first-time builders.

Sold by amiciKart — a trusted Indian electronics seller based in Noida — this BMS comes with a 1-year warranty and dedicated after-sales support. Order before 2 PM for same-day dispatch, with free shipping across India and Cash on Delivery available.

• Stay fully protected — built-in 4-in-1 safety guards your 4S Li-ion/Li-polymer pack against overcharge (4.25V cutoff), over-discharge (2.5V cutoff), overcurrent, and short circuits, preventing costly battery damage
• Power demanding loads with confidence — supports 15A continuous and 20A peak discharge current, making it perfect for solar lighting systems, DIY power banks, cordless tools, and portable power stations
• Charge faster and safer — compatible with 17–18V charging voltage and up to 10A charging current, so your battery pack tops up efficiently without risk of overheating or cell stress
• Extend battery pack lifespan — integrated active cell balancing keeps all 4 cells equalised during charge and discharge cycles, reducing cell mismatch and maximising the usable life of your 18650 battery pack
• Built for Indian conditions — operates reliably from -20°C to 80°C, making it suitable for both indoor electronics projects and outdoor solar or field applications across India
• Shop with complete peace of mind — backed by a 1-year warranty with dedicated Amicikart support, free pan-India shipping, same-day dispatch on orders before 2 PM, 30-day easy returns, and COD available