{"product_id":"4s-40a-bms-lithium-ion-battery-protection-board-with-cell-balancing-enhanced-version-14-8v","title":"4S 40A BMS Lithium-Ion Battery Protection Board with Cell Balancing (Enhanced Version \/ 14.8V)","description":"\u003cp data-path-to-node=\"5\"\u003eThe \u003cb data-path-to-node=\"5\" data-index-in-node=\"4\"\u003e4S 40A BMS \"Enhanced Version\"\u003c\/b\u003e is a highly versatile battery management system designed for 4-cell series (4S) Lithium-Ion battery packs. Striking the ideal middle ground between low-power 20A boards and bulky 100A industrial units, this 40A board is specifically engineered to handle the demanding electrical spikes of mid-sized DC motors. This makes it the undisputed go-to module for repairing, rebuilding, or upgrading cordless power tool batteries and high-power handheld vacuums.\u003c\/p\u003e\n\u003cp data-path-to-node=\"6\"\u003eThe \"Enhanced\" designation indicates that this board has been upgraded with specialized MOSFETs designed to handle heavy inductive loads and sudden current surges without falsely triggering the short-circuit protection—a common issue with standard protection boards when pulling the trigger on a drill. Furthermore, it features an integrated active cell balancing circuit that equalizes the voltage across all four series cells during the charging phase, ensuring maximum pack capacity and preventing premature cell failure.\u003c\/p\u003e\n\u003cp data-path-to-node=\"7\"\u003e\u003cb data-path-to-node=\"7\" data-index-in-node=\"0\"\u003eKey Features \u0026amp; Functional Advantages:\u003c\/b\u003e\u003c\/p\u003e\n\u003cul data-path-to-node=\"8\"\u003e\n\u003cli\u003e\n\u003cp data-path-to-node=\"8,0,0\"\u003e\u003cb data-path-to-node=\"8,0,0\" data-index-in-node=\"0\"\u003eEnhanced Motor Compatibility:\u003c\/b\u003e Upgraded circuitry prevents the BMS from falsely tripping and shutting down when subjected to the sudden, massive current spikes generated by starting heavy DC motors.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp data-path-to-node=\"8,1,0\"\u003e\u003cb data-path-to-node=\"8,1,0\" data-index-in-node=\"0\"\u003e40A Continuous Discharge:\u003c\/b\u003e Safely sustains heavy electrical loads up to 40 Amps, providing plenty of headroom for demanding applications without generating excessive, dangerous heat.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp data-path-to-node=\"8,2,0\"\u003e\u003cb data-path-to-node=\"8,2,0\" data-index-in-node=\"0\"\u003eActive Cell Balancing:\u003c\/b\u003e Automatically bleeds off excess voltage (at roughly 40mA per cell) from faster-charging cells during the top-off phase, keeping all four tiers perfectly synchronized at 4.2V.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp data-path-to-node=\"8,3,0\"\u003e\u003cb data-path-to-node=\"8,3,0\" data-index-in-node=\"0\"\u003eComprehensive 4-Tier Protection:\u003c\/b\u003e Constantly monitors the pack to instantly sever the connection in the event of over-voltage (over-charging), under-voltage (deep discharging), over-current, or a hard short-circuit.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp data-path-to-node=\"8,4,0\"\u003e\u003cb data-path-to-node=\"8,4,0\" data-index-in-node=\"0\"\u003eCompact Footprint:\u003c\/b\u003e Despite its high current rating, the board maintains a slim, flat profile that easily slides into the tight plastic casings of standard commercial power tool batteries.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp data-path-to-node=\"9\"\u003e\u003cb data-path-to-node=\"9\" data-index-in-node=\"0\"\u003ePerfect For:\u003c\/b\u003e\u003c\/p\u003e\n\u003cul data-path-to-node=\"10\"\u003e\n\u003cli\u003e\n\u003cp data-path-to-node=\"10,0,0\"\u003e\u003cb data-path-to-node=\"10,0,0\" data-index-in-node=\"0\"\u003eCordless Power Tool Rebuilds:\u003c\/b\u003e The absolute best choice for replacing the dead internal circuitry in 14.4V\/14.8V cordless drills, impact drivers, and circular saws.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp data-path-to-node=\"10,1,0\"\u003e\u003cb data-path-to-node=\"10,1,0\" data-index-in-node=\"0\"\u003eHigh-Power Handheld Vacuums:\u003c\/b\u003e Upgrades the internal power supplies of cordless vacuum cleaners to run on modern, high-capacity 18650 or 21700 lithium-ion cells.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp data-path-to-node=\"10,2,0\"\u003e\u003cb data-path-to-node=\"10,2,0\" data-index-in-node=\"0\"\u003eMid-Sized Robotics:\u003c\/b\u003e Provides a rugged, unthrottled power path for 12V-class robotic chassis utilizing multiple high-torque geared motors.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp data-path-to-node=\"10,3,0\"\u003e\u003cb data-path-to-node=\"10,3,0\" data-index-in-node=\"0\"\u003ePortable Audio Amplifiers:\u003c\/b\u003e Protects the internal 4S lithium power supply inside custom-built, high-wattage Bluetooth boomboxes.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp data-path-to-node=\"11\"\u003e\u003cb data-path-to-node=\"11\" data-index-in-node=\"0\"\u003eTechnical Specifications:\u003c\/b\u003e\u003c\/p\u003e\n\u003cul data-path-to-node=\"12\"\u003e\n\u003cli\u003e\n\u003cp data-path-to-node=\"12,0,0\"\u003e\u003cb data-path-to-node=\"12,0,0\" data-index-in-node=\"0\"\u003eConfiguration:\u003c\/b\u003e 4S (4 Cells in Series)\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp data-path-to-node=\"12,1,0\"\u003e\u003cb data-path-to-node=\"12,1,0\" data-index-in-node=\"0\"\u003eSupported Chemistry:\u003c\/b\u003e Lithium-Ion (18650, 21700, etc.) with 3.7V nominal \/ 4.2V peak rating\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp data-path-to-node=\"12,2,0\"\u003e\u003cb data-path-to-node=\"12,2,0\" data-index-in-node=\"0\"\u003eNominal Voltage:\u003c\/b\u003e 14.8V\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp data-path-to-node=\"12,3,0\"\u003e\u003cb data-path-to-node=\"12,3,0\" data-index-in-node=\"0\"\u003eFull Charge Voltage:\u003c\/b\u003e 16.8V (Requires a dedicated 16.8V CC\/CV lithium charger)\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp data-path-to-node=\"12,4,0\"\u003e\u003cb data-path-to-node=\"12,4,0\" data-index-in-node=\"0\"\u003eMaximum Continuous Current:\u003c\/b\u003e 40A\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp data-path-to-node=\"12,5,0\"\u003e\u003cb data-path-to-node=\"12,5,0\" data-index-in-node=\"0\"\u003ePeak \/ Instantaneous Current:\u003c\/b\u003e ~80A (For motor start-up spikes)\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp data-path-to-node=\"12,6,0\"\u003e\u003cb data-path-to-node=\"12,6,0\" data-index-in-node=\"0\"\u003eOvercharge Protection Threshold:\u003c\/b\u003e 4.25V ±0.05V per cell\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp data-path-to-node=\"12,7,0\"\u003e\u003cb data-path-to-node=\"12,7,0\" data-index-in-node=\"0\"\u003eOver-Discharge Cut-off Threshold:\u003c\/b\u003e 2.5V ±0.05V per cell\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp data-path-to-node=\"12,8,0\"\u003e\u003cb data-path-to-node=\"12,8,0\" data-index-in-node=\"0\"\u003eBalancing Current:\u003c\/b\u003e ~40mA per cell\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp data-path-to-node=\"12,9,0\"\u003e\u003cb data-path-to-node=\"12,9,0\" data-index-in-node=\"0\"\u003eDimensions:\u003c\/b\u003e Approximately 45 mm x 60 mm x 3 mm\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"K-TECHNICS","offers":[{"title":"Default Title","offer_id":42853818630215,"sku":null,"price":0.0,"currency_code":"KES","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0680\/7637\/2039\/files\/71KQ7XDIPCL._AC_SL1500.jpg?v=1780779452","url":"https:\/\/www.ktechnics.com\/products\/4s-40a-bms-lithium-ion-battery-protection-board-with-cell-balancing-enhanced-version-14-8v","provider":"K-TECHNICS","version":"1.0","type":"link"}