Our Top 15 Recommendations:
The 15 Best Onboard Battery Charger Reviews:
SaleBestseller No. 1 
NOCO GENIUS2D, 2A Direct-Mount Smart Onboard Car Battery Charger, 12V Automotive Charger, Battery Maintainer, Trickle Charger and Desulfator for AGM, Marine, ATV, Truck and Deep Cycle Batteries
- Meet the GENIUS2D - A direct-mount onboard battery charger for an under-the-hood battery charging. It's the all-in-one universal charging solution - battery charger, battery maintainer, trickle charger, float charger, plus battery desulfator.
- Do more with Genius - Designed for 12-volt sealed lead-acid automotive, marine, RV, and deep-cycle batteries, including flooded, gel, AGM, SLA, VRLA and maintenance-free batteries.
- Direct Mount - Securely mounts nearby the battery with its rugged snap-fit mounting bracket and effortlessly installs into most materials with truss-head self-tapping screws.
- Enjoy precision charging - An integrated digital thermal sensor detects the ambient temperature and alters the charge to eliminate over-charging in hot climates and under-charging in cold climates.
- Charge dead batteries - Charge batteries as low as 1-volt, including flooded, gel, and AGM, as well as automotive, marine, and deep-cycle batteries.
SaleBestseller No. 2 
NOCO Genius GENPRO10X1, 1-Bank, 10A (10A/Bank) Smart Marine Battery Charger, 12V Waterproof Onboard Boat Charger, Battery Maintainer and Desulfator for AGM, Lithium (LiFePO4) and Deep-Cycle Batteries
- Meet the GENPRO10X1 - Similar to our GEN1, only better. It's 41% smaller and delivers 33% more power. It's one of the best performing onboard marine battery chargers we have ever made.
- Multiple banks - A one-bank onboard battery charger rated a 10-amps - 10-amps per bank - for 12-volt batteries, including marine, boat, starter, and deep-cycle batteries.
- Charging modes - Independently charge and control each battery bank with selectable charging modes - including 12V, 12V AGM, 12V Lithium, and 12V Repair Mode - for all types of lead-acid and lithium-ion batteries.
- Enjoy precision charging - An integrated thermal sensor detects the ambient temperature and alters the charge to eliminate over-charging in hot climates and under-charging in cold climates.
- Charge dead batteries - Charges batteries as low as 1-volt. Or use the all-new force mode that allows you to take control and manually begin charging dead batteries down to zero volts.
SaleBestseller No. 3 
NOCO Genius GEN5X1, 1-Bank, 5A (5A/Bank) Smart Marine Battery Charger, 12V Waterproof Onboard Boat Charger, Battery Maintainer and Desulfator for AGM, Lithium (LiFePO4) and Deep-Cycle Batteries
- Meet the GEN5X1 - Similar to our GENM1, only better. It's 37% smaller and delivers 43% more power. It's one of the best performing onboard marine battery chargers we have ever made.
- Multiple banks - A one-bank onboard battery charger rated a 5-amps - 5-amps per bank - for 12-volt batteries, including marine, boat, starter, and deep-cycle batteries.
- Charging modes - Independently charge and control each battery bank with selectable charging modes - including 12V, 12V AGM, 12V Lithium, and 12V Repair Mode - for all types of lead-acid and lithium-ion batteries.
- Enjoy precision charging - An integrated thermal sensor detects the ambient temperature and alters the charge to eliminate over-charging in hot climates and under-charging in cold climates.
- Charge dead batteries - Charges batteries as low as 1-volt. Or use the all-new force mode that allows you to take control and manually begin charging dead batteries down to zero volts.
SaleBestseller No. 4 
NOCO Genius GEN5X2, 2-Bank, 10A (5A/Bank) Smart Marine Battery Charger, 12V Waterproof Onboard Boat Charger, Battery Maintainer and Desulfator for AGM, Lithium (LiFePO4) and Deep-Cycle Batteries
- Meet the GEN5X2 - Similar to our GENM2, only better. It's 37% smaller and delivers 43% more power. It's one of the best performing onboard marine battery chargers we have ever made.
- Multiple banks - A two-bank onboard battery charger rated a 10-amps - 5-amps per bank - for 12-volt batteries, including marine, boat, starter, and deep-cycle batteries.
- Charging modes - Independently charge and control each battery bank with selectable charging modes - including 12V, 12V AGM, 12V Lithium, and 12V Repair Mode - for all types of lead-acid and lithium-ion batteries.
- Enjoy precision charging - An integrated thermal sensor detects the ambient temperature and alters the charge to eliminate over-charging in hot climates and under-charging in cold climates.
- Charge dead batteries - Charges batteries as low as 1-volt. Or use the all-new force mode that allows you to take control and manually begin charging dead batteries down to zero volts.
Bestseller No. 5 
NOCO Genius GENPRO10X4, 4-Bank, 40-Amp (10-Amp Per Bank) Automatic Waterproof Smart Marine Charger, 12V Onboard Battery Charger, Battery Maintainer and Battery Desulfator with Temperature Compensation
- Meet the GENPRO10X4 - Similar to our GEN4, only better. It's 10% smaller and delivers 33% more power. It's one of the best performing onboard marine battery chargers we have ever made.
- Multiple banks - A four-bank onboard battery charger rated a 40-amps - 10-amps per bank - for 12-volt batteries, including marine, boat, starter, and deep-cycle batteries.
- Charging modes - Independently charge and control each battery bank with selectable charging modes - including 12V, 12V AGM, 12V Lithium, and 12V Repair Mode - for all types of lead-acid and lithium-ion batteries.
- Enjoy precision charging - An integrated thermal sensor detects the ambient temperature and alters the charge to eliminate over-charging in hot climates and under-charging in cold climates.
- Charge dead batteries - Charges batteries as low as 1-volt. Or use the all-new force mode that allows you to take control and manually begin charging dead batteries down to zero volts.
SaleBestseller No. 6 
NOCO GENIUS GENPRO10X2, 2-Bank, 20A (10A/Bank) Smart Marine Battery Charger, 12V Waterproof Onboard Boat Charger, Battery Maintainer and Desulfator for AGM, Lithium (LiFePO4) and Deep-Cycle Batteries
- Meet the GENPRO10X2 - Similar to our GEN2, only better. It's 19% smaller and delivers 33% more power. It's one of the best performing onboard marine battery chargers we have ever made.
- Multiple banks - A two-bank onboard battery charger rated a 20-amps - 10-amps per bank - for 12-volt batteries, including marine, boat, starter, and deep-cycle batteries.
- Charging modes - Independently charge and control each battery bank with selectable charging modes - including 12V, 12V AGM, 12V Lithium, and 12V Repair Mode - for all types of lead-acid and lithium-ion batteries.
- Enjoy precision charging - An integrated thermal sensor detects the ambient temperature and alters the charge to eliminate over-charging in hot climates and under-charging in cold climates.
- Charge dead batteries - Charges batteries as low as 1-volt. Or use the all-new force mode that allows you to take control and manually begin charging dead batteries down to zero volts.
SaleBestseller No. 7 
NOCO Genius GEN5X3, 3-Bank, 15A (5A/Bank) Smart Marine Battery Charger, 12V Waterproof Onboard Boat Charger, Battery Maintainer and Desulfator for AGM, Lithium (LiFePO4) and Deep-Cycle Batteries
- Meet the GEN5X3 - Similar to our GENM3, only better. It's 37% smaller and delivers 43% more power. It's one of the best performing onboard marine battery chargers we have ever made.
- Multiple banks - A three-bank onboard battery charger rated a 15-amps - 5-amps per bank - for 12-volt batteries, including marine, boat, starter, and deep-cycle batteries.
- Charging modes - Independently charge and control each battery bank with selectable charging modes - including 12V, 12V AGM, 12V Lithium, and 12V Repair Mode - for all types of lead-acid and lithium-ion batteries.
- Enjoy precision charging - An integrated thermal sensor detects the ambient temperature and alters the charge to eliminate over-charging in hot climates and under-charging in cold climates.
- Charge dead batteries - Charges batteries as low as 1-volt. Or use the all-new force mode that allows you to take control and manually begin charging dead batteries down to zero volts.
Bestseller No. 8 
SOLAR 1002 1.5 Amp 12V Automatic Onboard Battery Charger
- Permanently mount your battery charger to your battery
- Simply plug in power to an extension cable for fast, automatic charging and maintaining
- Automatic operation. No need to press any buttons.
- Battery attachment kit included
SaleBestseller No. 9 
NOCO Genius GENPRO10X3, 3-Bank, 30A (10A/Bank) Smart Marine Battery Charger, 12V Waterproof Onboard Boat Charger, Battery Maintainer and Desulfator for AGM, Lithium (LiFePO4) and Deep-Cycle Batteries
- Meet the GENPRO10X3 - Similar to our GEN3, only better. It's 27% smaller and delivers 33% more power. It's one of the best performing onboard marine battery chargers we have ever made.
- Multiple banks - A three-bank onboard battery charger rated a 30-amps - 10-amps per bank - for 12-volt batteries, including marine, boat, starter, and deep-cycle batteries.
- Charging modes - Independently charge and control each battery bank with selectable charging modes - including 12V, 12V AGM, 12V Lithium, and 12V Repair Mode - for all types of lead-acid and lithium-ion batteries.
- Enjoy precision charging - An integrated thermal sensor detects the ambient temperature and alters the charge to eliminate over-charging in hot climates and under-charging in cold climates.
- Charge dead batteries - Charges batteries as low as 1-volt. Or use the all-new force mode that allows you to take control and manually begin charging dead batteries down to zero volts.
Bestseller No. 10 
AUTOGEN 2-Bank Marine Battery Charger, 10-Amp (5-Amp Per Bank) Dual Battery Trickle Charger Maintainer, 6V & 12V Onboard Battery Charger and Battery Maintainer
- 【2-Bank, 10-Amp】10 Amp (5 Amp per bank) on-board battery charger for charging and maintaining two 6V/12V batteries independently.
- 【Widely Batteries】Safely charge and maintain all types of Lead-acid batteries, including wet, gel, AGM, and deep-cycle batteries. Marine battery charger is also a great choice for Cars, Trucks, RV, Boats, Yachts.
- 【Automatic Voltage Detection】Auto select 6V/12V mode without keying button, it automatically determines the correct voltage for your target battery. Two bank charger output 2 x 5A depending on the condition of each battery. Constantly regulated voltage patterns allow the battery to be recharged fully and safely without fear of overcharging.
- 【Monitor Power Levels】Solid state two-color LED light indicates the state of the charge. Continuous charging, unlimited time, automatically enter the power maintenance mode after full, extend the battery life, worry-free battery charger for daily use.
- 【Multiple Security Protection】Multiple security protection, such as over current protection, overcharge protection, overheat protection, reverse connection protection, short circuit protection. Rugged and 100% waterproof, waterproof coefficient reach IP65.
SaleBestseller No. 11 
Logitech G305 LIGHTSPEED Wireless Gaming Mouse, Hero 12K Sensor, 12,000 DPI, Lightweight, 6 Programmable Buttons, 250h Battery Life, On-Board Memory, PC/Mac - White
- HERO Gaming Sensor: Next-gen HERO mouse sensor delivers up to 10x the power efficiency over other gaming mice with exceptional accuracy and responsiveness thanks to 400 IPS precision and up to 12000 DPI sensitivity
- LIGHTSPEED Wireless: Ultra-fast LIGHTSPEED Wireless technology gives you a lag-free gaming experience. The G305 wireless gaming mouse delivers incredible responsiveness and reliability with a super-fast 1ms report rate for competition-level performance
- Ultra-Long Battery Life: The G305 wireless Logitech mouse boasts an incredible 250 hours of continuous gameplay on a single AA battery so you can play at peak performance without worrying about running out of power
- Lightweight design: Thanks to an efficient mechanical design, the G305 gaming mouse weighs in at only 99 grams for high manoeuvrability
- Portable Convenience: The durable, compact design with built-in USB receiver storage makes the G305 means you can take it with you.
Bestseller No. 12 
dkplnt 20A 12V to 24V DC to DC Boost Converter On-Board Battery Charger for Flooded, Gel, AGM, and Lithium, Using Multi-Stage Charging in RVs, Commercial Vehicles, Boats, Yachts with Acc Control
- Input Voltage: 11-16v DC（can be connected to 12V battery/auto generator）
- output Voltage：28v DC （During the charging process, the charging voltage of the battery will gradually increase until it reaches 28V）
- Multi-Chemistry Battery Types: AGM, Flooded, Gel, and Lithium
- Over current protection, Over voltage protection, Over temperature shutdown
- High efficiency up to 97%. Aluminium shell with epoxy potting and waterproof IP68
SaleBestseller No. 13 
Renogy 12V 40A DC to DC On-Board Battery Charger for Flooded, Gel, AGM, and Lithium, Using Multi-Stage Charging in RVs, Commercial Vehicles, Boats, Yachts, 40A
- 【Compatible Multiple Battery Types】 Compatible with a multitude of alternator types, the DC-DC battery charger offers correct charging for AGM, Flooded, Gel, and Lithium batteries.
- 【Smart 3-stage Charging】 The DC-DC battery charger will charge your house batteries from the starter battery by 3-stage charging (Bulk, Boost, and Float), to make sure it optimally and automatically charge to 100%.
- 【Various Protections For Ultra Safety】 Offers Over-voltage Protection, Over-temperature Protection, and Reverse Polarity Protection to ensure the operation safety. It also isolates the input and output to prevent voltage transmission errors and interfere with house battery charging.
- 【Protect Your Starter Battery】The DC-DC battery charger is capable of identifying whether the generator is started, to prevent over-discharge of the starting battery and protect the generator.
- 【Reliable Quality】The compact and robust design makes it suitable for all conditions. CE certification.
Bestseller No. 14 
Guest 2707A Guest On-Board Battery Charger 8A / 12V, 2 Bank, 120V Input
- 12V 8 amp 2 bank on-board battery charger
- Built-in safety: reverse polarity, over-current, over-voltage, over-temperature and ignition protection. In-line fuses for maximum DC wire protection
- 100% Waterproof (IP67) and shock resistant for all fresh and saltwater applications
- Dedicated battery charging, sensing and control per bank
- For all 12 volt flooded and AGM lead acid batteries. 2 year warranty
Bestseller No. 15 
ProMariner 44012 ProSport HD Waterproof Marine Battery Charger, 12 Amp, 2 Bank
- ProSport HD 12A Dual Bank Waterproof Marine Battery Charger (Part Number 44012) replaces the old ProMariner Gen 3 ProSport 12 (part number 43012)
- ProMar Digital Technology: Microprocessor and software controlled charging technology for fast, precise charging
- Distributed-On-Demand Technology: 100% of all available charging amps are utilized by distributing unused charging amps to any one or combination of all batteries as needed
- Heavy Duty Tri-Surface Extruded Heat Sink Design: Upper, lower and rear facing heat sink design for optimal cooling while delivering true rated constant current charging amps during its two charge mode
- Expanded LED Display with Completion Status Gauge: LED fuel gauge style completion status. Four color multi-stage mode LED status bar. Multi-stage Charge Mode, System Check OK, individual Battery Status and Battery Type indication
Last update on 2023-01-12 / Affiliate links / Images from Amazon Product Advertising API