It was a cold, rainy night when my car suddenly sputtered and shook like an unhealthy horse. I managed to pull it over to the side of the lonely country road, but the engine went silent. No matter how much I turned the key, its efforts resulted in nothing but a faint click. My heart sank as I realized the battery was completely dead. If only I had kept my battery charger in the trunk like my dad always nagged me to, I wouldn’t be stranded!
Having a good automotive battery charger on hand can mean the difference between getting back on the road quickly and waiting hours for a tow truck. Not only can they resurrect a dead battery, quality chargers also help maintain optimal battery health when your car, boat, RV or other vehicle sits unused for weeks at a time. But with so many models and features to consider, how do you choose the right one?
This comprehensive guide will highlight the top 5 battery chargers ideal for automotive use. You’ll learn what features to look for, plus tips for safely using and maintaining your charger. I’ll also answer some of the most frequently asked questions about battery charging. Read on to revive your battery knowledge!
How to Select the Best Automotive Battery Charger
Before jumping into the top picks, let’s discuss how to select a charger tailored to your specific needs. When making your choice, keep the following key factors in mind:
Types of Batteries
The first consideration is whether you need a charger designed for standard lead acid batteries or for newer lithium ion and gel varieties. Matching the charger voltage and charge levels to the battery type is crucial for effectiveness and safety.
Amperage and Voltage
Look for a charger offering at least 10 amps, with adjustable voltage settings like 2/6/10V or 2/4/6/8/10/12V. Higher amperage charges the battery faster. Multiple voltage settings allow you to safely charge different sized batteries.
If you’ll use the charger on the go, choose a compact, lightweight model rather than a large stationary unit. Look for handles and a neatly contained set of clamps, cords, and accessories.
Any battery charger you buy should have protection against short circuiting, overcurrent, overcharging, and reversing polarity (attaching leads backwards). Advanced “smart” chargers have microprocessors that automatically monitor conditions and adjust the current to optimize charging and safety.
Clamps vs. Plugs
Basic chargers have clamps that attach to the battery terminals, while more advanced ones have a harness that plugs into the cigarette lighter or battery harness outlet. Plugs are simpler to use, while clamps give flexibility to attach to any battery.
Some high-end chargers run diagnostics on the battery to test for problems and determine if it might need replacement soon. This is useful, but adds to the cost.
Price and Warranty
Like most things, you get what you pay for when it comes to chargers. That said, you can find quality basic models for under $50 while advanced professional units run over $200. Check the warranty length too, ideally 1 year or longer.
OK, now that you know what to look for in a battery charger, let’s review the top contenders available for automotive and similar uses. For each, I’ll highlight the stand-out features, pros and cons.
The Top 5 Automotive Battery Chargers
1. NOCO Genius G3500
The NOCO Genius G3500 lives up to its name as a super smart charger. While pricier than basic models, it delivers excellent performance and safety. Here are the highlights:
- UltraSAFE – Monitors battery health to avoid overcharging. Meets strict safety protocols.
- Advanced Diagnostics – Runs tests to detect battery defects and determine state of health.
- Simple Controls – Intuitive dash-mounted interface and controls
- Lightweight – Compact and portable at just 2.4lbs
- Universal Fit– Can charge any 6V or 12V flooded or maintenance-free lead-acid battery
- Backed by 5-Year Warranty
Pros: Very safe and efficient charging, highly advanced diagnostics, lightweight and portable, charges all common battery types.
Cons: Higher price tag, display can be hard to interpret.
Overall, the innovative diagnostics and ultra-safe charging make the NOCO Genius G3500 one of the best options if you have the budget for it. It’s a very robust and fully-featured charger suitable for home workshop pros and demanding vehicle owners alike.
2. Battery Tender Plus
The Battery Tender Plus is a simple, fully automatic battery float charger ideal for routine maintenance of stored vehicles. Key features include:
- Fully Automatic – Hook up and walk away. Monitors voltage and turns itself off when fully charged.
- 4-Step Charging – Initial bulk charge, then absorption, float, and maintenance modes optimize battery health.
- Safe for Long-Term Use – No risk of overcharging or undercharging when left connected. Great for seasonal vehicles.
- Compact Size – Light and portable for easy storage and transport.
- LED Indicator Lights – Easily see charging mode and battery status at a glance.
- 1.25 Amp Charge Rate – Slower than a charger for dead batteries but fine for maintenance.
Pros: “Set and forget” fully automatic operation. Great for maintaining charge without supervision. Very affordable price.
Cons: Too slow to effectively charge a fully dead battery. Only useful as a maintenance float charger.
For keeping stored or seasonal vehicles ready to go at all times, the Battery Tender Plus is hard to beat. It’s simple, affordable, safe for continuous use, and compact. Just plug it in and let the automatic intelligence do the rest!
3. Clore Automotive Battery Charger
When you need serious charging power for heavy duty vehicles, the Clore Automotive Battery Charger delivers. It’s packed with professional grade features:
- 100 Amp Engine Start – Cranks up to 7L gas engines or 5L diesel even with weak batteries.
- 75 Amp Rapid Charging – Brings deeply discharged batteries to full charge in about an hour.
- Automatic or Manual – Starts in automatic mode then switches to manual finish charge.
- Dual Analog Ammeters – Display charge status and current load at a glance.
- Rugged and Durable – Water and dust resistant for shop use. Steel case withstands abuse.
- Safety Timer – Automatically turns off if battery doesn’t reach set voltage in 7 hours, avoiding overcharge risks.
Pros: Extremely powerful and fast charging. Handles large automotive batteries with ease. Provides engine jump starts. Rugged shop quality construction.
Cons: Very bulky and heavy. Overkill for small vehicles and basic charging needs. Requires monitoring during manual finish charge.
For DIY mechanics, auto shops, and anyone needing to charge or start big trucks, RVs, farm equipment and more, the Clore Automotive Charger is a workhorse. Though costly and cumbersome, it has the power and stamina to handle just about any charging job.
4. Schumacher Fully Automatic Battery Charger
The Schumacher Automatic Battery Charger combines convenience, versatility and affordability. Features include:
- Fully Automatic – Microprocessor controlled multi-stage charging detects battery state and adjusts current for safe, optimal charging. Just hook up and start charging.
- Compatible With All Battery Types – Works with standard, AGM, gel and deep-cycle lead acid batteries.
- Multiple Charge Rates – Switch between 2A/10A settings to match battery needs. 10A for fast charge and 2A for small batteries.
- Float Mode – Safely maintains 100% charge after initial charging stage is complete. Prevents discharge when connected over extended periods.
- Reverse Hook-Up Protection
- Compact Size – Lightweight and easy to store under the seat or in the trunk.
Pros: Good versatility to automatically charge all common battery types at variable rates. Compact yet powerful enough for full charging. Affordable price point.
Cons: Not the most heavy duty or rugged build quality. Slow charge time compared to higher amp alternatives.
For an affordable yet versatile automatic charger suitable for all personal vehicles, the Schumacher unit is a great choice. Convenient set-and-forget charging in a compact package.
5. SOLAR BA9 Portable Solar Car Battery Charger
For an eco-friendly charging solution, check out the SOLAR BA9 Portable Solar Car Battery Charger. Why is this handy?
- Dual Panel Solar Design – Unfold and align panels towards sun for maximum power generation.
- Pedal Power Option – Manually generate charge by repeatedly pressing on pedals. Great backup when sun is low.
- Ultra-Portable – Folds into compact rectangular block for storage in vehicle. Weighs only 2.2 lbs.
- 12V Output – Enough power to trickle charge 12V batteries when sunlight is available. Green energy!
- LED Indicators – Show charging and battery status clearly.
- Cigarette Lighter Plug – Convenient plug-in connector fits most vehicles.
Pros: Provides renewable solar energy charging on the go. Ultra-compact and lightweight. Silent operation. Also charges via pedal power as a backup.
Cons: Very slow charge capacity compared to electric chargers. Useless at night or on overcast days. Not suitable as sole battery charger.
The SOLAR BA9 Portable Solar Charger makes a great emergency backup for off-grid charging situations. While it lacks the power of full-sized electric chargers, the green energy and silent operation are big perks!
Using and Maintaining Your Charger
Now that you’ve chosen the perfect battery charger, let’s go over some tips for safe operation and upkeep:
- Carefully review the manual and follow all instructions. Don’t skip steps!
- Protect against sparks – Charge away from flammable fumes, preferably outside.
- Ensure proper ventilation while charging. Gases can build up.
- Use protective eyewear – Batteries can burst and send acid spraying. Serious eye hazard!
- Avoid getting battery acid on skin or clothes – Contains sulfuric acid. Rinse immediately with water if contact occurs.
- Keep children and pets away from charging area.
While specific steps depend on your model, the general process is:
- Turn off any devices drawing power from the battery. Shut off engine and accessories.
- Clean battery terminals and remove any corrosion.
- Connect charger leads to battery terminals, ensuring proper polarity (+ and -). Red lead to positive, black to negative.
- For manual chargers, select appropriate voltage or setting.
- Plug in and turn on charger. Let it run through the charging cycle. Monitor automatic models for errors or abnormal behavior.
- Disconnect when fully charged. Check lights for charge confirmation.
- Reinstall battery if it was removed from vehicle during charging.
Maintenance and Storage
- Check battery and alternator health – Have them tested if uncertain. A weak alternator can drain a good battery.
- Keep corrosion at bay – Clean battery posts and cable connectors periodically with a wire brush. Reapply protective grease.
- Recharge batteries every 1-2 months when vehicles are stored long term. More frequently in hot climates.
- Exercise the battery with occasional full charges, not just float charges. This helps prevent sulfation buildup.
- Store properly when not in use – Keep charger unplugged in a dry, temperate area away from children and pets.
- Inspect regularly for any damaged parts or frayed/melted wires. Don’t use a faulty charger!
Frequently Asked Questions
Let’s wrap up this battery charger guide by answering some common questions:
How long does a full charge take?
It depends on the charger’s amperage rating and the capacity of the battery. For a fully dead battery, expect 6-12 hours with a 2 amp charger or 2-4 hours with a 10 amp charger. Larger capacity batteries require longer charge times. If the battery has any charge remaining, it will take less time to top off.
Can I overcharge my automotive battery if I leave the charger on too long?
Quality automatic chargers will switch to a float or maintenance mode once the battery reaches full charge, preventing overcharge damage. But it’s still smart to stay nearby and disconnect once the ‘charged’ indicator confirms completion to be safe. Don’t leave any charger unattended for more than a day when first using it until you verify it stops charging properly.
What voltage and amperage settings should I use to charge a 12V car battery?
For most 12V lead acid batteries, a setting of 12 to 14 volts and 6 to 10 amps is ideal for a reasonably quick charge without stressing the battery. Always start on the lower settings first before increasing voltage or amperage. Very large truck or marine batteries may benefit from a 15 amp or higher charger when time is limited.
Are automatic “smart” chargers worth the extra cost?
Absolutely, the extra investment is worthwhile. Automatic multi-stage charging increases safety by preventing overcharging and monitors your battery’s needs instead of blindly pumping in maximum current. This extends battery lifespan. They’re very convenient too – just connect and charging starts without fiddling with settings.
If my car battery is completely dead, will a charger revive it?
In many cases, yes. Leave the charger on for several hours and the battery may slowly regain enough charge to start the vehicle. However, if the battery was in poor condition or deeply discharged for an extended time, it may be too far gone and need replacement.
Is it safe to charge a battery in the rain or snow?
Never charge a battery when it’s exposed to rain, snow or standing water. This risks dangerous electric shocks. Always charge in a dry covered area. Even moisture in the air can carry current. If the battery needs to stay in the vehicle during charging, keep the hood up so the charger and connections stay entirely dry.
How can I tell when my battery is fully charged?
The best way is to look for an indicator light or display on the charger base that confirms charging is complete and it has switched to float or standby mode. Chargers that lack an indicator may need you to periodically check the voltage readout on the clamps once it reaches 14+ volts to confirm it’s holding steady.
Let the Current Flow!
With the right automotive battery charger, you’ll spare yourself the headaches of being stranded roadside or having to constantly jump start your car during short trips. Carefully assess your needs in terms of charging power, portability, and features. Study the top recommended models in this guide, and you can confidently choose a quality charger to keep your battery woes at bay.
Remember to always take proper safety precautions, follow charging procedures carefully, and maintain your equipment. Apply this advice, and your vehicles will have reliable power ready to bring their engines roaring back to life!