The United States Army has a large number of diesel and gasoline vehicles in parking lots in many countries. Each one of them is likely to have at least one lead battery. The problem is batteries go dead from when they stand idle. This is costing the tax paying public $26 million in replacements annually. However. US army lead batteries could last six to eight years on trickle charge.
Solar Patent for US Army Lead Batteries

United States Army researchers applied for a smart controller patent on November 21, 2019. Their device could govern power from a small solar panel to a bank of vehicle batteries, according to Tech Link. Like most simply good ideas we wonder why this one took so long to emerge.
There are US army lead batteries starters in a vast array of humvees, mine-resistant ambush protected vehicles, and trucks to mention but a few. We understand three quarters of these travel less than 3,000 miles a year. Hence the Army spends $26 million in battery replacements to keep the fleet rolling ready.
However a Net Saving of $17 Million a Year Is Feasible
Army vehicles often have powerful radios running through lead batteries too, not to mention other electronic devices presumably. These offer more solar trickle charging opportunities. That’s because Tech Link explains a below-charge battery can affect the efficacy of this sophisticated equipment too.

United States technology-transfer laws allow agencies to license patents to their suppliers. Therefore, there appears to be strong likelihood of US army lead batteries trickle-charging off solar panels soon. We really like this innovation because it is something we could achieve real soon.
Moreover, this innovation could prove handy to powerboat owners mothballing for winter, and also the motorcycling fraternity. We find it amazing what we can achieve, when we side-line our old thinking and imagine what we could do instead.
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Trickle Charging Your Battery to Keep It Charged
Charging Lead-Acid Battery Banks
Preview Image: Internally Transportable Vehicle