12 Volt Battery Charger Comparison Guide
We have put together these comparison charts on Battery Chargers that are designed to maintain and sometimes even improve the power of your RV, boat, car, truck or SUV battery. We have included the top manufacturers of battery chargers which include BatteryMinder (made by VDC Electronics), NOCO and Battery Tender (made by Deltran). We have evaluated products from all 3 companies and found quality, functionality & reliability to be excellent by all three manufacturers. Products are grouped in small wall outlet units and the larger separate case and plug chargers. These charts will give you a better understanding of the available functions each unit has relative to the price of the product. See Below for a detailed description of what each specification in the chart means.
Remember, these battery chargers are designed to maintain batteries, they are not quick recover chargers you would need to get a completely dead car battery charged in a hurry. Small charger/maintainers are used to keep batteries in good shape when they are going to sit without use over time. Seasonal items such as lawn tractors, boats, RV's and vehicles in storage will all benefit from these battery chargers.
Please Note: specifications & prices are subject to change without notice, please use these charts as a reference only.
Output Volts: The voltage that the charger puts out, this will correlate with the voltage of your battery. A question brought up often: Can a 12v charger be used with (2) 6v batteries and the answer is yes when those 6v batteries are wired in series.
Output Current: This is the power that the charger puts out measured in Amps. The more output current the faster a battery requiring charging will be back to full capacity.
Input Voltage: The voltage required to power the battery charger
Input Current: The power that the charger will use at maximum charging, measured in Amps.
Minimum Battery Voltage : This is the lowest voltage a battery can have to be recharged by one of these chargers
Display Information: Details provided by the charger to keep you informed on the status of the battery or charger.
Diagnostic Mode: The ability of a battery charger to test a battery to determine it's condition.
Absorption Mode: A point in the charging process that takes a battery to full charge by way of a slightly higher voltage but decreasing current so as to not overheat the battery.
Maintainer Mode: A constant voltage (varies depending on the battery type) is maintained with very little current (less than 1% of the batteries capacity) for extended periods to keep a battery at full capacity.
Desulfation Mode: The removal of sulfation that has accumulated on the lead plates that leads to battery failure. Both Batteryminder and NOCO use high frequency electronic pulses to remove this and ultimately extended battery life.
Desulfation Type: The two best known ways of desulfation is high frequency electronic and high voltage pulses. At present time it is believed that electronic pulses are a much more efficient and thorough way of doing this
Short Circuit Protection: This is also known as spark protection which does not allow the charger to begin charging before the connections have been completely made.
Reverse Polarity Protection: If the charger senses that the leads have been put on the wrong side of the battery it will not try to charge the battery.
Temperature Protection: When the ambient temperature of the air gets to extreme levels (whether that is cold or hot) the charger goes into a mode to lessen the chances for battery damage.
Over Charge Protection: A feature that shuts off the charger if full charge is not achieved after a specific period of time.
Flooded / Deep Cycle: This is the most common battery type found in RV's (commonly called house or coach batteries) and requires a user to monitor the water level replenishing as needed.Maintenance Free / Sealed: This type of battery is common in vehicles as a starting battery and is sealed so it does not require any maintenance.
AGM / Gel: AGM stands for absorbent glass mat and are a very efficient deep cycle batteries which are maintenance free. These react differently than lead-acid batteries and require a different type of charging. Make sure to select a charger designed to charge AGM batteries.
# of Batteries: All chargers can charge multiple batteries, but you must ensure that they are the same type and capacity when doing so. You also have to consider if there will be any parasitic load on the batteries and if the charger you selected can cover those power requirements. And last that they are connected properly together to equal the chargers output voltage.
Temperature Sensor: The ability to remotely monitor the batteries temperature ensuring that it is never over or under charged or experiences overheating. This is best done with a sensor placed on the battery versus in the unit itself.
Cord Length: This will help in determining how close the battery needs to be to the power source. All battery charger companies frown on using any type of extension cord, so check with the manual on how to do this safely.
Battery Installation: What type of method is provided to attach the charger to the battery. Grip Clips are a fast way to attach to a battery but can work loose. Terminals are attached to the battery post or battery terminal and provide a secure installation that will not come disconnected.
Weather Proof Case: Not everyone has a nice cozy garage to charge in and so you may want to look at weather proof chargers for outdoor applications.
Operating Temperature: This is the manufacturers recommended operating temperature for each type of charger.
Car/ Truck / RV Battery Charger Comparison