Solar Battery Tender Review

Deltran Battery tender has been in business for almost 50 years and has provided iconic and well-known battery chargers.  For a company that pegged itself on innovation, the solar battery tender remained unchanged over a long period of time. 

First of all it only came with mounting screws and you obviously can’t screw on your windshield or on your bike.  They were also charging extra for the cables and you had to buy the charge controller separately.

What was once a game changer over time became a bulky, expensive and cumbersome item. Mounting it was a challenge and the control box was too exposed.  The new 12v 17-watt solar battery tender fixes the misses of the old model.  Not only is it more budget-friendly but it has added features to make it easier to mount on a car or motorcycle and keep your batteries topped off safely even for weeks.

Here are some of those great features:

Features of the new solar battery tender

Easy Mounting

The new battery tender has several options for mounting. If you are using it in your Car or RV you can use the suction cups to mount on the windscreen. It also has a handlebar bracket to easily mount on a motorcycle one of the few solar chargers you will get with this option.

Solar Panel on Car Dashboard
Solar Charger on a Wind Shield

The ball-mount clamping system also allows to mount the panel on handles or metal frame and adjust it towards sunlight.

Blocking Diode

It is important as the Solar Panel charges the battery that is does not drain the battery at night. A blocking diode prevents reverse charging.

LED Indicator

An LED indicator saves you a lot of time in getting to know the charging status and whether it is working at all. The solar battery tender comes with a solid state two-color LED Light that not only indicates the charging status but the battery voltage as well.

Efficiency rate

The Solar panel is efficient and allows for charging in  even low light and cloudy conditions.

Compatible with Different Battery types

The Solar Battery tender can keep a LifeP04, and Lead acid batteries including Sealed AGM and Gel batteries. You can even connect batteries in storage in parallel and it will be able to maintain them as long they are stored when fully charged.

Built in Micro-controller

The controller is the most important part in a solar system. It protects the battery from being overcharged and controls the rate of charging.  The battery tender comes in with a 3- microcontroller that switches the charger between bulk when the battery is the battery has a low voltage, absorption when almost fully charged and float when fully charged.


The charger is weatherproof/waterproof that ensures it can be used in outdoors without damaging the panels. It also comes with a built in compensation sensor.

OBD II Connector

With the OBD II connector you don’t have to connect to the batteries directly.  The OBD II connector also comes with 3 amp fuse for extra protection.


It comes with a long cable (about 10 feet) that allows you to mount

How to use

The solar battery tender is great device to have to keep your batteries topped up. It is important to note that this does not charge a battery but acts as a trickle charger that prevents it from dying. Also it is not to be used when the battery has a load rather because of the small discharge when batteries are left idle.


Car batteries discharge slowly when not in use this is compounded by some devices like alarms and clocks that continue to drain the battery.  It is therefore important to top up the losses with a trickle charger.

Mount the panel where it can get sufficient sunlight. This can be on the windshield using the suction cups or just placing it on the dashboard. To charge your car battery you’ll need to hook up the batteries using the O-ring terminals.  If your car has an OBD II port you can use it to plug in straight using the OBD II connector.

You can leave it for weeks and you won’t find a dead battery and your car will be ready to go.


 As stated before the 5 watt solar battery tender is one of the best options for charging a motorcycle.  The handlebar mount is life saver when charging a motorcycle battery in the outdoors.  Just connect to your battery using the clips and leave it charging your battery. 

Your bike will be ready to go even if you leave it for days without using.

Lawn Mower

Lawn Mowers spend most of their time in storage and not may we use them only a few times a year. But you don’t want to be jump starting your lawn mower every time you need to use it.  You can use the screw mount to place the solar panels on the outside while the lawn mower is stored.

Some of the Cons of the Solar Battery tender

While the new 5 watt is an upgrade what was a downgrade was the replacement of the aluminum casing with plastic.  Plastic does not necessary do well in the open sun but I am yet to see any effect.  The LED light is also a little dim and you have to strain to make out if it is charging.

While this is a good charger I would still recommend the Suner Power Solar Car battery charger for charging a car battery. This is especially if your car has cigarette lighter plug and don’t want to go under your hood to charge your battery.  The mounting cups are also a bit stronger compared to the Solar battery tender and greater efficiency in low light and cloudy conditions.