It is never fun or pleasant when a car battery, medical equipment, solar power supply, security system, marine vehicles, or any battery runs out. Especially in emergency situations.
It can be particularly dangerous to recharge a battery – in particular, if the user isn’t well versed in charging batteries. It is always best to be prepared with the best (and easiest to use) products available which is why this article covers the reviews and comparisons of the best deep cycle battery chargers on the market as well as offers a deeper insight as to the best charger on the list and why.
A deep cycle battery is a battery designed to produce constant power over an extended period of time which drains the battery remarkably and it needs to be recharged again in order to complete the charging cycle. Essentially, they steadily discharge power slowly over a period of several hours at a time.
All of the products in this article are deep cycle battery chargers which means they aren’t equipped to handle hot, rapid charging situations which means they might never reach a full capacity charge and will instead show that the battery is charged before it reaches full capacity. This is very important to note if you’re reading reviews of these items as some people claim they do not charge completely.
COMPARISON CHART
![]() |
NOCO Genius GEN1
|
CHECK PRICE ▼ |
NOCO Genius G3500 Battery Charger and Maintainer
|
CHECK PRICE ▼ | |
Foval Automatic Trickle Battery Charger
|
CHECK PRICE ▼ | |
Battery Tender Junior 021-0123
|
CHECK PRICE ▼ | |
Schumacher SC1281
|
CHECK PRICE ▼ |
Specification
Color: | Black |
Product Dimensions: | 1 x 1 x 1 inch |
Item Weight: | 6.83 Pounds |
Model: | GEN1 |
Brand: | NOCO |
Voltage: | 12 volts |
One of the top, best deep cycle battery chargers out there is the NOCO Genius due to its size, durability, technology, and safety features which, when combined, make it top of the market.
WHAT WE LIKE
The size of 1 x 1 x 1 inch makes it very portable and the IP68 waterproofing technology makes it extra durable. It is able to charge multiple types of lead-acid batteries: AGM, gel, wet, and deep-cycle. It has advanced safety protection features and durability.
WHAT WE DONT LIKE
Unfortunately, there is a problem with the battery overheating in rare cases which the company is currently working on fixing.
PROS
- Small and portable
- IP68 waterproof and NEMA 6p
- Charges multiple types of lead-acid batteries
- Top-of-the-line safety features
CONS
- Rare cases of battery overheating
Specification
Color: | White/black/red |
Product Dimensions: | 7.7 x 2.7 x 1.9 inches |
Item Weight: | 2.15 Pounds |
Model: | G3500 |
Brand: | NOCO |
Voltage: | 12 volts |
Like the first product on the list, this charger is a NOCO. However, this white, black, and red charger is different from the charger above with its repair mode, versatility, and diagnostic technology and is a great deep cycle battery charger for almost any situation.
WHAT WE LIKE
The battery charger has an advanced repair mode that repairs the negative, damaging effects on batteries that were left uncharged for long periods of time.
It also works with multiple types of voltage – 6 and 12. It has a diagnostic feature that intuitively detects reverse polarity, damaged, and low-voltage batteries. Its seven modes diversify its abilities to fit all battery charging needs.
WHAT WE DONT LIKE
While there is a five-year warranty on this charger, like many online warranty policies, it is difficult to get ahold of the company and it takes a long time through the lengthy process of returning the item to actually get money back.
PROS
- Repair mode
- 6-volt and 12-volt
- Diagnostic technology
- 7 modes
CONS
- Long and lengthy warranty and return process
Specification
Color: | Black/red |
Product Dimensions: | 3.9 x 2.4 x 1.2 inches |
Item Weight: | 0.6 pounds |
Model: | BC01B-1 |
Brand: | Foval |
Voltage: | 12 volts |
For a charger that fits most cars, is spark-proof, has multiple charge modes to fit your needs, and weighs less than a pound, this deep cycle battery charger is a great choice.
WHAT WE LIKE
This charger offers four charge modes (initialization, bulk charge, absorption mode, and float mode) along with its multi-level protection against short circuit, reverse polarity, overvoltage, and overcurrent for a safer and smarter battery charge.
Along with being safe, it has a quick disconnect harness to disconnect the charger in seconds in case of emergency. The charger is also ISM (infinite sequential monitoring) adaptable which means that it changes its voltages with the battery’s needs.
WHAT WE DONT LIKE
This charger needs to be watched or monitored while it is charging. It lacks a switch to turn off the power/charging mode when the battery is full and ends up draining/killing the battery altogether.
PROS
- ISM adaptable
- Quick disconnect
- Four charging modes
- Multi-level safety protection features
CONS
- No “battery full so stop charging” function
Specification
Color: | Black/green |
Product Dimensions: | 8 x 4 x 9 inches |
Item Weight: | 1.8 Pounds |
Model: | 021-0123 |
Brand: | Battery Tender |
Voltage: | 12 volts |
With a spark-proof design, many safety measures in place, and a quick, easy, and simple design, this battery charger is a great product for any 12 voltage charging needs.
WHAT WE LIKE
When playing with fire (or, in this case, electricity), it is essential to know when too much is too much. This battery charger has LED lights to communicate: a red and a green light that blink or stay steady depending on the message the machine wants to communicate.
Plus, it has many safety features designed in it such as a spark-proof design which means it won’t spark the user or any item until the charger detects voltage from the battery. The charger not only charges but also maintains the charge in some items such as a car and a PWC.
WHAT WE DONT LIKE
Unfortunately, the Battery Tender Junior isn’t always reliable, which might be okay if it is not for emergency use, but can be detrimental to the situation if you’re stuck and the charger does not work. The battery also stops working in 12-18 months sometimes after moderate use. So, depending on how often it is used, it might not be worth buying a new one in a year or so.
PROS
- LED colored light communication
- Spark-proof safety features
- Maintainer and charger
CONS
- Not durable
- Unreliable
Specification
Color: | Black/red |
Product Dimensions: | 11 x 10 x 8 inches |
Item Weight: | 12.65 pounds |
Model: | SC1281 100 |
Brand: | Schumacher |
Voltage: | 12 volts |
This battery charger is one of the top on the market due to its automatic smart technology which provides this product with a 100A engine starter, 30A boost maintainer, and an auto desulfator advanced diagnostic testing feature.
WHAT WE LIKE
This product ensures the safety of its users with a reverse hook-up protection feature which means the charger won’t operate if the clamps are reversed. It is easy to use and works for standard, AGM, GEL, and deep-cycle batteries.
It is entirely automatic with a microprocessor-controlled system that adjusts the charge and amperage. It communicates using a digital screen and LED indicator lights.
WHAT WE DONT LIKE
Weighing in at over 12 pounds (5.4 kilos), this battery is the heavier one on the list. The digital battery display is inaccurate in some cases and shows a battery is at a certain percentage for hours, then when disconnected and reconnected, it shows it is at 100% charged.
PROS
- Safety features
- Versatile battery compatible
- Automatic technology
- LED light and digital screen communication
CONS
- Heavy weighting
- Inaccurate digital battery display
Final Verdict
While this list is not extensive, it is obvious that the best deep cycle battery charger is the NOCO Genius GEN1. This is principally due to its size, durability, variety, and safety features.
Although it weighs 6 pounds, which is one of the heavier chargers on the list, it is only 1 x 1 x 1 inches which means it is incredibly small and portable. This battery is IP68 waterproof which means it is able to withstand sand/dirt/dust and can be submerged in up to 1.5 meters of water for 30 minutes since it is completely sealed and impenetrable.
The charger is also rated NEMA 6P which is considered equal to IP68. It is able to not only charge deep-cycle batteries, but also all lead-acid batteries such as AGM, gel, and wet batteries, too.
Since electricity is dangerous to play with, the charger has advanced safety features put in place including overcharge, reverse polarity, ignition, and thermal protection, as well as spark-proof technology.