BatteryMINDer Model 12248: 12Volt 8 Amp Wet/Gel/AGM Charger/Maintainer/Desulfator

12248Battery chargers come in many types: Bulk Chargers, trickle chargers, and smart chargers like BatteryMINDer.

Bulk chargers are designed to quickly recover from a “dead” battery. They tend to have little sophistication, just pouring out lots of energy quickly. This is fine for bringing up a partially discharged battery and getting the car started quickly. But such brutes may overcharge the battery if left on for extended periods. And, they may not have temperature compensation. The bottom line, they may ruin a battery if left connected for extended periods – like the four months I need to store my car.

Trickle chargers try to tackle the storage problem. Prior generations of these chargers just used a low-current charger with a maximum voltage output. These “weak” chargers simply don’t have the power to quickly recharge a battery, but are reasonable at keeping one “full” under some conditions. They are cheap and somewhat effective.

Neither of these dumb chargers deal with significant details of maintaining a battery’s charge. The voltage of a fully charged battery varies with temperature – about 12.5mv per degree. That doesn’t sound like much, but over the 100 degree temperature variation that is possible with the car in storage, this is 1.25 volts – a significant voltage difference. If the charger’s set point is too low, the battery will discharge; if too high, the battery will get too much energy and will over-heat. Such heat kills batteries by boiling off the water in the battery fluid.

The “Smart Chargers” such as BatteryMINDer, solve these problem with a micro-controller. They sense the state of charge in the battery, the outside temperature, and adjust charging accordingly. The BatteryMINDer provides all of the charge phases listed above, and adds two more: a Qualification phase and a desulfidization phase.

I really like the 12248 charger since it does all types of batteries and lets you select the charging amperage as well. The BatteryMinder also desulfates batteries which the Optima chargers (my alternative option at the time) do not. The BatteryMinder works very well and comes with a temperature sensor as well. The only thing that would be nice is if they added an integrated battery level display. I highly recommend this charger due to its versatility, it has the potential to save a person a lot of money by extending the life of various batteries (auto, lawn, deep cycle, etc).  I actually received this as a gift.. it really is the perfect gift – no one usually likes to spend money on things such as battery chargers but when you receive something like this – its a great surprise.

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