Best Battery Tender Junior – Top 5 Picks for 2020

This is our official list in search of the best battery tender junior on the market today. Scroll further down for full details on each product as well as a handy guide to battery tenders.

Quick Look:

  1. Battery Tender 021-0123 Battery Tender Junior
  2. NOCO Genius G3500 6V/12V 3.5A
  3. Deltran Battery Tender Junior 12 Volt 3-Pack
  4. Extreme Max 1229.4000 Battery Budd
  5. Battery Tender 022-0197 8V 1.25 High Efficiency

We know time is of the essence, so the above is a cheat sheet of what’s ahead, just in case your’re in a hurry. Otherwise, keep scrolling down for more detailed and constructive info on each item.

5 Highest Reviewed Battery Tender Juniors to Consider

With the best battery tender, you can intelligently charge your vehicle’s battery, and since a battery tender charges a 12v battery with amps, you don’t have to worry about overcharging the battery and causing unnecessary damage.

Safety is also very important, and the best battery tenders should have some sort of protection against sparks. Below, you’ll find reviews for the top five battery tenders available.

1.) Battery Tender 021-0123 Battery Tender Junior

Battery Tender 021-0123 Battery Tender JuniorHere we have a top product, and once it’s finished charging your battery, it will automatically switch to float mode. This product makes it easy to find out what stage it’s in because it features two bright LED indicator lights. The Battery Tender 021-0123 is spark proof and protects against reverse polarity.

It comes with a 12-foot output cord, and it’s one of the best products for most types of batteries. The circuitry in this tender can handle sealed, flooded and lead-acid batteries, and with the help of an onboard computer, it always sends a safe level of power to your battery.

It also features ISM adaptive charging, which changes the power output hundreds of times per second. Before supplying power, this device checks for a correct connection, and the quick-connect harness can be removed in seconds. This product can work great for boats, tractors, cars, SUVs, ATVs and scooters.


  • Never delivers power with an incorrect connection
  • Perfect for winter charging
  • Great gift
  • Works for most batteries


  • Uses brute force to charge a battery

($) Check price on Amazon

2.) NOCO Genius G3500 6V/12V 3.5A

NOCO Genius G3500 6V 12V 3The NOCO Genius G3500 features a streamlined design, and it’s compatible with many batteries. You can use this product for cars, motorcycles, lawnmowers and ATVs, and it can even be used for powersport, RV, marine and automotive batteries.

The NOCO Genius G3500 is one of the safest battery tenders available, and it can easily charge six and 12v lead-acid and lithium-ion batteries. When compared with standard chargers, this product functions at twice the speed, and it can even be used to repair damaged batteries.

With the help of an onboard microcomputer, this product closely monitors your battery and automatically reduces energy consumption. To prevent injuries, it’s equipped with several safety features, and it features a portable, lightweight and compact design.


  • Can be left on for long periods of time
  • Perfect for deep-cycle batteries
  • Charges dead batteries very quickly
  • Small and lightweight


  • Doesn’t work on fully drained batteries

($) Check price on Amazon

3.) Deltran Battery Tender Junior 12 Volt 3-Pack

Deltran Battery Tender Junior 12 Volt 3-PackThe Deltran battery tender junior works for several different types of batteries and comes with the required harnesses. Since this product is a genuine Deltran brand, it’s made with premium components and it serves as a two-stage lead-acid battery charger.

With an automatic three-step charging program, it will charge your dead battery, and when it’s finished, it will switch to float mode. The Deltran battery tender can be used on flooded lead, AGM and sealed batteries, and after your battery reaches peak voltage, the charger will automatically switch to float.

A simple LED light tells you the state of charge, and with reverse polarity protection, it prevents unnecessary damage to your battery. The Deltran battery tender comes with a long power cord, and it’s even designed to be spark proof.


  • Perfect for classic cars
  • Great for cold climates
  • Can make your battery last much longer
  • Superior dependability


  • Not compatible with some batteries

($) Check price on Amazon

4.) Extreme Max 1229.4000 Battery Budd


Extreme Max 1229 4000 Battery BuddyThe Extreme Max 1229.4000 battery tender is engineered for long-term battery storage, and it can effectively charge and maintain batteries in any climate. If you’re looking for something to charge your cars, motorcycles, UTVs, ATVs and boats, then this product is worth considering.

It features four intelligent charging modes, and when it’s finished charging your battery, it will automatically switch to maintenance mode. The Extreme Max 1229.4000 is compatible with small and large batteries, and it can handle six and 12v lead-acid, sealed and flooded batteries.

It’s even designed with a regulatory internal safety circuit, but it won’t work for batteries that have a voltage under three volts. This product is great for generators, marine units and powersports, and it’s one of the top battery tenders for all types of batteries and vehicles.


  • Never overcharges the battery
  • Great for riding lawnmowers and similar equipment
  • Includes gator clips for an easy connection
  • Excellent choice for winter storage


  • Not compatible with some batteries

($) Check price on Amazon

5.) Battery Tender 022-0197 8V 1.25 High Efficiency

Battery Tender 022-0197 8V 1 25 High EfficiencyThe Battery Tender 022-0197 is an 8v device, and it’s rated for 1.25 amps. If you’re looking for a way to safely charge and maintain your battery, then this product is worth considering. Since it’s classified as a high-efficiency charger, it has no trouble charging most batteries, and it’s great for keeping a fleet charged throughout winter.

If you don’t own a fleet, you can always use it to charge an ATV, riding lawnmower or classic car. Many six-volt batteries are swapped out for an eight-volt replacement because the stronger batter offers faster cranking and starts.

The Battery Tender 022-0197 is designed to charge an 8v battery, and once it has fully charged the battery, it will switch to maintenance mode and deliver a steady supply of electricity. This device can prevent the hassle that comes from having to buy a new battery for stored vehicles.


  • Great for golf cart batteries
  • Lightweight plug doesn’t fall out of the outlet
  • Couplings are easy to setup
  • Perfect for maintaining 8v batteries


  • Some components could be made better

($) Check price on Amazon

Brief Guide to Buying Battery Tenders

Every battery is designed to store and discharge electrical energy, and the battery inside of your vehicle is no exception. As electricity is transferred into your vehicle’s electrical components, it’s called electrical current, and it’s the force that powers the stereo and electronics.

Over time, a battery loses its electrical charge, which can stop your vehicle from starting. If you don’t use your car for many months, there is a good chance you’ll need to buy a new one.

What Is a Battery Tender?

Battery tenders are devices that ‘tend’ to your vehicle’s battery when it is sitting for long periods without being used. They plug into a standard AC outlet and feed the battery voltage in the form of amps, but they are not the same as the older kind of trickle feeders which would feed a constant dribble of voltage to your car’s battery.

Instead, battery tenders are intelligent and monitor how full your battery is. If it needs a lot of charge they will fill it right up, but if it only needs a little they will just give it a small amount. This is better for rechargeable batteries as it won’t over-charge them and cause damage.

The main purpose of this device is to condition a battery that you don’t plan to use for a long time. For example, maybe you want to store an RV, boat, motorcycle or car away for the winter, and you don’t want to babysit the vehicle throughout this period of time.

Over time, a battery will lose its charge, and this happens when its left inactive for many months. Since cold air has a negative impact on a battery, it will lose its charge even faster during the months of winter. As the name would imply, a battery tender is designed to tend to the battery while you’re gone.

To stay fresh and charged, your battery must be cared for, and with a high-quality battery tender, you can make sure it receives the care it needs.

How Are Battery Tenders Intelligent?

There are several features that make a battery tender smart, and with the help of sensors, it can easily monitor a battery and supply it with ample power.

The best battery tender will have a microprocessor, and it can constantly adapt itself to meet the electrical needs of the battery. Many consumers mistake trickle chargers for battery tenders, and the problem with trickle chargers is that they’re much more likely to ruin your battery.

In many cases, these devices overcharge the battery and cause it to boil out. A battery tender is different because it actively monitors the battery’s charge and adjusts accordingly.

Features to Consider

Most battery tenders offer four major modes, and once you understand the different modes and what they’re used for, you’ll know exactly how to use your own tender. Initialization mode performs several tests and checks to make sure your battery is working properly.

Bulk charge mode is used when the battery is low, and it will deliver maximum power to quickly charge the battery. After the tender has charged the battery up to a certain level, it will switch to absorption mode and begin dropping the amps.

This process will continue until the optimal voltage level is reached, and after the battery is at the perfect voltage level, the tender will switch to float mode and supply just enough voltage to keep the battery charged.

What to Look For?

With a variety of products to choose from, it’s important to know what to look for. When shopping for a high-quality battery tender, many consumers make the mistake of not thinking about what they need. Some products might only offer one feature that is essential for your needs, but others offer a long list of useful features.

By paying attention to the features, you can save a lot of money and pay for features that you need. First, you need to make sure you’re buying the right tender for your specific battery. Depending on your vehicle, you might have a sealed, flooded or lead acid battery. If your vehicle sits outside then you want to make sure you have a waterproof battery so that it won’t be damaged or short circuit due to damp weather and rain.

There are also several other types of batteries, and if you purchase the wrong product, you could accidently ruin your battery. The most popular type of battery tender is designed for a standard 12 volt battery, but there are other types that are meant for smaller batteries such as you find in motorcycles and lawn mowers, and specialised 6 volt battery tenders for vintage vehicles with old-style batteries.

Another feature to consider is the peak amperes, and a higher number for this rating can indicate the presence of better components, which is a good sign. Do you need your battery to be charged quickly? For example, if you have a wheelchair that needs to be charged after use? Or is it just that you need to keep your battery in good condition over a few months when you’re not using it? This will help you decide whether you want a battery tender that feeds the voltage slowly, or one that can charge your battery fast when needed.

If you want a faster charge, then you should pick a product with a higher amp rating, as a general rule. There are some products which are adjustable, so you can change whether you need a smaller or larger output.

Who Can Benefit?

If you know that you will not be using your vehicle for some time – typically for more than a month – then one of these devices would benefit you. When batteries are left for long amount of time without being used they lose power gradually, and cold weather accelerates this process. If your battery discharges too much you can end up with a dead battery, and this can also mean that your security system won’t work either.

A battery that has discharged slowly and has not been maintained well can fail and leave you stranded somewhere. A battery tender will keep your battery in working order, even if you go for 6 months without using your vehicle. You can have confidence when you next use your vehicle, that it will be fully charged.

Often motorcycle owners will keep a battery tender hooked up to their motorcycle when it is parked, and it means they can rest knowing that the security system will work well, and it will be easy to start again when they want to use it. Deltran have had reports from motorcycle owners that before they used a battery tender they would have to replace their battery every 6 months, but once they kept it maintained properly with an intelligent charger, it would last three years or more.

What To Avoid?

Don’t be misled into buying a trickle charger instead of a battery tender. These can ‘fry’ your battery as they constantly trickle voltage into them, whereas battery tenders are intelligent and turn off once it is charged.

Never use a battery tender unless it matches the voltage of the battery you are charging. For example don’t use a 6 volt battery tender with a 12 volt battery.


What’s the difference between battery tenders and other types of battery chargers?

Battery Tenders are intelligent chargers. With most chargers, you would need to unplug them once the device is fully charged. But what if you are not around to unplug it? And what if it slowly loses its charge and will need recharging again before you’re able to plug in the charger?

Intelligent chargers monitor the state of the battery and help you out. As Wikipedia explains, ‘The output current of a smart charger depends upon the battery’s state. An intelligent charger may monitor the battery’s voltage, temperature or time under charge to determine the optimum charge current and to terminate charging.’ (‘Battery Charger’, 2017)

How do I find the right size charger for my battery?

This can be quite complicated if you get into the details. So look at the manufacturer’s recommendations for what the charger should be used for. A general recommendation is for a battery to be charged at 20-25% of the battery’s Ah capacity.

How do I know if my battery charger is safe?

You can look out for various safety features when you buy the battery charger. Some safety features include reverse polarity protection, spark protection, a safety timer, and certification from the FCC, UL/CSA.

How do I use a battery tender?

It is important that you connect the wires to the correct terminals, or you may get sparks and thereby damage the battery. Positive cables should be connected to positive and negative to negative. You can find some basic instructions on how to use them with your vehicle at Further instructions can be found in product manuals or on the manufacturer’s website.

How long can I keep my battery tender plugged in?

In theory you should be able to leave your battery tender plugged in as long as you want and not worry about it, as they are designed to be left to look after themselves. However it is recommended that you check on them every couple of weeks if you can, so that if something breaks or fails you can do something about it.

Why do batteries lose their charge?

There are many reasons batteries in vehicles lose their charge. Sometimes lights can be left on or there may be drains in the electrical system. Batteries can also have corroded or loose connections and can be weak or not very well looked after, and weak batteries will also get worse in extreme hot or cold weather.

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Wrapping Up

The best battery tender can save you money because it eliminates the need to buy new batteries. It works well for most batteries, and it’s especially useful for fleet owners.

If you need to maintain a lawnmower, ATV, car or recreational vehicle, consider getting a high-quality battery tender. With the right product, you can avoid the headache of having to deal with a dead battery.