BLACK & DECKER BM3B 6V and 12V Automatic Battery Charger / Maintainer Review

BLACK & DECKER BM3B 6V and 12V Automatic Battery Charger / Maintainer Review

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1) A true float charger unlike chargers that uses a trickle maintenance mode.
2) Built-in circuit protection guards against overcharging, reverse polarity, or short circuit; ETL certified for performance and safety.
3) AC low voltage compensation ensures maximum performance when used with an extension cord.
4) The maintenance voltage is dependent upon Full Charge Voltage (FCV) of the battery (from 12.6 to 13.2) depending on design & how much sulfation has taken place on the internal plates.
RATINGS: 4.0 out of 5 Stars

Have you ever found yourself stuck in a situation where your vehicle just refused to move, and the problems you sorted out came to be a dead battery? Or when you bring your vehicle out of the garage for the winter season and the battery is fully discharged, unable to help start the engine? If in such a situation you could not find a nearby auto mechanic shop for the solution, what would you do?

Having one of the top smart battery charger in your vehicle with you is something that can save you from these unpredictable conditions. The Black & Decker BM3B 6V and 12V Automatic Battery Charger and Maintainer is something that is the solution to all these problems. It will not only bring your dead batteries to life, but it can also help maintain your working batteries for you.

DC connector accessory which comes with it gives you a vast set of options for either re-charging or maintaining any battery. The different connectors makes it also a practical “charger/maintainer” for every kind of car batteries for example: RVs, Motorcycles, Specialty Cars, Lawn Mowers, Marine Deep Cycle Batteries & Water-Crafts.

Features of the BLACK & DECKER BM3B Battery Charger / Maintainer

Now that you know the why and when you need a battery charger, you might be making up your mind to purchase one. But before that, you need to find out which are the best options for you when it comes to the best vehicle chargers as there are so many versions available in the market.

Before we start with the discussion of features and specs you need to learn a few things about chargers. The most suitable charger is the one that is easy to use, is not too big to keep with you, is fast in charging and has some excellent display to indicate the status of the battery.

Now let us have a look at the features and specs of Black & Decker bm3b Battery Charger & Maintainer and learn whether it meets best standards or not.

  • Automatic Switching

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Black & Decker BM3B Battery maintainer and Charger saves you from the trouble of keeping a check on the status of the battery. All you have to do is to connect the terminals of the battery to the charger, and the process will start all by itself.

You can plug the charger and get off to your work as the battery takes a couple of days to charge and you cannot keep sitting by its side. When the battery gets fully charged, the charger automatically switches from charging mode to float mode, and thus the battery does not get over charged even if you are not there to detach it from the charger.

  • It Can Charge Variable Batteries

The charging capability is not limited to a single kind or voltage of the battery instead it can quickly charge a 6V and 12V batteries. The variance of the nature of batteries is not a problem either as the BM3B battery charger/maintainer can facilitate AGM, GEL and WET batteries without the slightest trouble.

  • An Amazing Size

What makes a charger most desirable is its compactness and small size. The BM3B battery automatic battery charger and maintainer comes in a very sleek model that you can comfortably hold it in your hands. You can carry it with you on travel or place it in your car’s trunk, and it will occupy a minimal space.

  • Ease of Use

Another great feature of The BLACK+DECKER BM3B is that it is effortless to operate. You do not have to make complete connections with the battery, and these are not a dozen step before the charging could start.

All you have to do is to connect the terminals to the battery and turn on the supply. The charger will carry on with its work until the battery is full.

  • Smart Charging

It comes with a smart charging technology that enables you to charge the battery without the fear of overcharge. The charger intelligently knows about the optimal charge, and it keeps the battery at that optimal charge during charging.

  • Auto Switching

This charger has a feature that is known as the automatic switching operation. The function of this operation is to switch the charger from charging mode to float mode. The float mode is the mode that helps the charger to avoid from overcharging, and when the battery gets fully charged, it dissipated some charge and ceased any further charging.

  • Included Mounting Bracket

A significant issue for the charger could be the placement of the battery maintainer if you are in some far-fetched area. The BLACK & DECKER BM3B 6V & 12V Battery Charger / Maintainer comes with a built-in mounting bracket that you can use to place the charger in and get free of trouble.

  • Vehicles Supported

When you ask about the vehicles for which Black &Decker BM3B 6V Battery Charger is supportive too, you will be glad to know that this charger can charge the batteries of almost all the vehicles. You can use it to charge the dead or slightly discharged batteries of the cars, trucks, vans, minivans, motorcycles, boats or any other vehicles that you desire.

  • Safety Concerns

One of the major issues in regular chargers is the short circuit and the way they pose a threat to the safety of the user. BM3B Charger and Maintainer has a special circuit to prevent overcharging the battery, and the reverse polarity helps break the circuit and eliminates any chances of the short circuit during the charging process.

  • Loads of Included Accessories

The package comes with three connector sets, so you do not have to fuss around to find the suitable ones. These include DC accessory plug, battery clips and battery terminal rings.

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Why is Black & Decker BM3B 6V, 12V Battery Charger And Maintainer The Best Choice?

Getting a dead battery in your vehicle when you are in a rush is something that could bother you a lot. So the BLACK & DECKER BM3B 6V and 12V Automatic Battery Charger/Maintainer is the answer to all your worries about charging. If you have no idea which battery you can connect to the charger and how long you need to keep it connected to get the battery fully charged, this fantastic charger can take care of all these things without you not having to attend to it all the time.


  • The price is right for what it does.
  • The small, ruggedly built and it’s compact size makes it easy to carry
  • Fully automatic
  • No supervision required during the operation
  • Package comes with three different connectors
  • The charging ability will boost your battery within 30 minutes. Hence, you’ll never face a car starting problems whenever it has been attached to your battery.


  • Connecting wires could be small
  • The body could be fragile
  • Although does not support PWC and AGM batteries, but the good news is that the manufacturer is working to sought it out soon.


Now that you have had a look at the salient features of The Black & Decker BM3B 6V and 12V Battery Charger / Maintainer, the decision to purchase one for yourself would not be hard. It is a handy and straightforward solution not only to maintain your running batteries but also to bring the dead ones back to life.

With least supervision and ease of connectivity, this fantastic charger is ruling the market and is standing with other smart battery chargers in competition with Deltran Battery Tender, Battery Tender Junior Battery Chargers and the NOCO Genius G3500 Ultra Safe Smart Charger. With the slight difference in the prices, these all chargers are selling like hotcakes, and people are rushing to buy them.




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