Putting OPTIMA's Digital Battery Chargers to the Test
Batteries are one of those things that most people don’t give much thought until something goes wrong. Whether your vehicle is a dedicated trail rig or a daily driver Accord, we’ve probably all experienced a dead battery at least once; maybe you deep-cycled a starting battery too many times, left your lights on all night, or let it sit too long between charges.
A good “smart” battery charger and maintainer is a key piece of equipment to extend the life of your battery. Less expensive battery chargers can sometimes do more harm than good. We recently had the opportunity to test out OPTIMA’s Digital 1200 and 400 models 12V Performance Charger and Maintainers on two deeply discharged OPTIMA batteries. The batteries were so deeply discharged that the chargers wouldn’t even recognize them.
The chargers are specifically designed to enhance the performance of OPTIMA and other high-performance flooded and AGM batteries. We use OPTIMA's RedTop and YellowTop series batteries as they are completely sealed and better fit to handle the demand and heat of off-road conditions. Since OPTIMA uses Sealed Absorbed Glass Mat (AGM), they won't spill or degrade like traditional flooded batteries. While the RedTop is best suited for a daily driver where frequent starting is needed, the YellowTop is ideal for secondary vehicles that may sit or have a slow constant draw. These make them ideal for expedition rigs.
Charging a Deader-Than-Dead Car Battery
We have a car that we forget to drive sometimes. We have much more fun in our Jeep, so the car gets neglected and parasitic drain completely killed the battery while it was sitting. Many chargers won’t charge a battery that has less than 10.5 volts, but the OPTIMA chargers will recognize and charge a battery that is as low as 1.25VDC.
This battery had less than 1.25VDC, so we had to hook up a second battery in parallel (positive-to-positive, negative-to-negative) to start the charging process. Of course, we could always use another vehicle to jump-start the car and let the alternator charge the battery enough for the charger to recognize it, but alternators are designed for battery maintenance, not battery charging, and it’s always good to know an alternative method.
Using Optima’s Digital 1200 & Digital 400 Battery Charger
After charging the battery to 75 percent with the Digital 1200 model, we decided to switch to the smaller Digital 400 model, because we could leave the charger in place with the hood closed; hidden out of sight there’s less worry about someone being tempted to steal it.
OPTIMA claims that their chargers can recover deeply discharged batteries that other chargers can’t, and sure enough, we were able to fully charge this battery after our other charger wouldn’t.
Keeping Your Car Battery Maintained
We probably did some long-term damage by allowing the battery to deeply discharge in the first place, but now we can put the Digital 400 in maintenance mode when we are not driving the car, and it will float charge the battery. The charger automatically recognizes when the battery is in storage and desulfates the battery. It will recondition the battery for up to three hours once every 30 days, then return to float mode.
Most battery failures are due to the build-up of lead sulfate crystals on the battery plates that occurs when a battery is not at full charge. Not all battery chargers perform desulfation, so it’s an important feature to look for if your vehicle isn’t driven often, such as a dedicated trail rig not used daily.
Oops, We Did It Again
A few weeks later, we did a real bone-head move (a friend said to blame it on the Mercury in retrograde). While tearing apart the driveshafts on our Jeep to replace the U-joints, one of us left the ignition switch on for two days, with several electronics plugged in and drawing power. We have a Genesis dual-battery kit, but didn’t pay attention to the fact that the batteries were isolated at the time. Using a multi-meter to measure the voltage in the two batteries showed the problem.
Once again, we had a battery that was below 1.25VDC, and the charger showed a fault. There wasn’t even enough battery power to get the isolator to reconnect the batteries.
Again, we hooked up a second battery in parallel, this time used it to jump start the Jeep, and then hit the Boost button on the Genesis G-Screen to reconnect the batteries. That was all we needed to get the Digital 1200 charger started. We let the 1200 charger sit overnight, and by morning the battery was fully charged.
There’s no worry about over-charging a battery because the multi-stage charging process automatically goes into maintain mode when charging is complete. Since the batteries in the Jeep are OPTIMA YellowTop batteries designed for deep cycling, the long term effect of allowing the battery to deeply discharge this one time is less of a concern.
Now, we're using the Digital 1200 to charge up the battery we had used to recover the other two batteries.
Optima’s Digital 1200 vs. Digital 400
The Digital 400 charges at a maximum of 4 amps, and the Digital 1200 charges at a maximum of 12 amps. The 1200 is faster (OPTIMA says it is up to 2X faster than most chargers of similar size), but it’s also much larger. The 400 has a wall mount hook that also functions as a stand to prop the charger up when it’s on flat surface. The 1200 has a USB charging port for charging cell phones and tablets (iPad and iPhone compatible), an integrated light on the positive charging clamp and an additional auxiliary maintainer port for a hardwired maintainer connection. They both feature well-designed cable storage for neat freaks like me who can’t stand having loose cords.
Optima 12V Performance Charger and Maintainer Review
Additional great features:
- Reverse polarity protection
- Over-temperature protection
- Spark free connection
- Automatic restart in case of power failure
- Temperature compensation
- Quick set, single touch operation makes the chargers very easy to use in both charge and maintenance e-modes
- LCD display is easy to read and understand
- Includes cables with alligator clamps, ring terminals and aux
Six fully automatic modes that the charger will sequence through:
- Stage 1 – Analyze battery’s condition
- Stage 2 – Soft ramp charging control for deeply discharged batteries when needed
- Stage 3 – Fast charge (normal) for moderately discharged batteries
- Stage 4 – Conditioning mode when charging is complete
- Stage 5 – Auto maintain, float mode
- Stage 6 – Automatic storage recognition mode, desulfates battery
The OPTIMA Digital 1200 and 400 12V Performance Charger and Battery Maintainers can be used on any standard flooded or AGM 12v battery. There are Quick Settings for the following battery types:
- High Performance AGM starting batteries (OPTIMA RedTop and BlueTop with dark gray body)
- High Performance AGM deep cycle batteries (OPTIMA YellowTop and BlueTop with light gray body)
- Standard flooded lead-acid and AGM batteries – large
- Standard flooded lead-acid and AGM batteries – small