SUNAPEX 12V Solar Battery Charger: 20W Waterproof Solar Panel Kit – Aluminum Trickle Charger for Car Battery with Controller – Battery Tender Motorcycle Boat Marine RV Trailer Tractor Truck

Price: $34.97
(as of Feb 06, 2026 15:55:39 UTC – Details)

Product description

Which batteries can be charged by this solar panel system?

Most 12V rechargeable batteries：Lead-acid batteries (such as AGM, GEL, SLI, Marine Battery, Deep Cycle Battery, etc.), lithium batteries such as LiFePO4

Is this solar panel system safe? Will it overcharge my batteries?

Our solar panel system is very safe. The controller includes overcharge protection. When the battery is fully charged, the controller automatically stops charging, preventing any risk of overcharging.

Why did I measure over 20V from my 12V solar panel?

The 20V is the open-circuit voltage of the solar panel. It does not the charging voltage applied to the battery by the solar panel system. To measure the charging voltage, ensure that the solar panel system remains connected to the battery.

At what voltage will the controller stop charging the battery?

For a 12V battery, the controller will stop charging when the battery voltage reaches around 14.2V, indicating that the battery is fully charged. When the battery voltage drops to a maintainable level, the controller will resume charging.

Can this 12V solar system charge multiple batteries simultaneously?

Yes. You can connect multiple batteries in series or parallel. Keep in mind that the combined battery voltage will always remain at 12V. For example, you can either connect two 6V batteries in series or parallel multiple 12V batteries.

SUNAPEX Solar Panel System

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Price

$34.97$34.97

$49.99$49.99

$59.99$59.99

$49.97$49.97

$49.99$49.99

Power

20W

25W

30W

20W

10W

Voltage

12V

12V

12V

12V

12V

Open Circuit Voltage

21-22V

21-22V

21-22V

21-22V

21-22V

Maximum Power Current

1.11A

1.39A（Solar Panel)

1.67A

1.11A

0.56A

Cell Type

Monocrystalline

Monocrystalline

Monocrystalline

Monocrystalline

Monocrystalline

Controller Type

PWM Controller

MPPT Controller

PWM Controller

PWM Built-in Controller

PWM Built-in Controller

Dimensions

13.6*15 inches

14.17*16.73*0.67 inches

14.6*16.37 inches

13.4*14.4*0.06 inches

21.06″D x 4.92″W x 13.98″H

Weight

4.52 lb

4.27 lb

6.30 lb

1.18 lb

1.2 Pounds

Waterproof

✔

✔

✔

✔

✔

Portable

✘

✘

✘

✔

✔

Aluminium Frame

✔

✔

✔

✘

✘

Smart PWM Trickle Charger System: This 12V solar battery charger features advanced PWM technology to prevent overcharging and battery drain. Automatically stops charging at full capacity (100% indicator light) and reactivates when voltage drops – perfect as a battery tender charger for car/RV/marine batteries
All-Weather IP67 Waterproof Design: Both solar panel and controller are IP67 waterproof, surviving heavy rain/snow/hail. The corrosion-resistant aluminum frame and tempered glass ensure 25-year durability even in coastal marine environments
Multi-Device Battery Savior: Keeps mighty mule gate opener, electric fences, lawn mower batteries, and RV solar panel kits charged. Includes 3 connectors: 12V cigarette lighter plug, alligator clips, and O-rings
Real-Time Charging Visualization: The solar charger controller shows precise battery levels (25%/50%/75%/100%) with dual-status lights. Blue = sunlight detected, Red = trickle charging in progress
360° Adjustable Solar Panel Kit: This 20W solar panel kit’s bracket rotates 360° for optimal sun angles. Pre-drilled holes fit roofs/boats/trailers. Protective corners prevent fall damage
Extended 25-Year Lifespan: Military-grade aluminum frame and solar-powered tempered glass outperform standard small solar panels in UV/impact resistance
Effortless Plug-and-Play Setup: Install this portable solar battery maintainer in 5 minutes with included screw kit. No wiring expertise needed for 12 volt systems
Wide Voltage Compatibility: Works with all 12V solar batteries (LiFePO₄/AGM/GEL/SLA) for cars/trucks/ATVs. Ideal for solar electric fence chargers
Complete Solar Trickle Charger Kit: Includes a 12V solar panel; 1 charge controller; 1 cigarette lighter; 1 alligator clips; 1 O-rings; 1 mounting bracket; 1 screw kit; 1 User Manual and 4 protective corners – everything for trickle charger for motorcycle battery
24/7 Lifetime Support: Backed by lifetime technical support for your rv solar panels kit for 12 volt system. 24-hour response guarantee