US 5,260,637 · Granted 1993-11-09
The 1993 Supercapacitor Patent That Powers Car Starter Motors
This patent describes a way to use a supercapacitor—a device that stores electrical energy really fast—to give car electrical systems an instant power boost when they need it. Instead of relying only on your battery, a supercapacitor charges up quickly and releases huge amounts of energy for a short burst, like when you're cranking an engine or powering an accessory that needs a lot of juice all at once.
The plain-English version
What it protects
The claim covers a car electrical system that combines a rechargeable battery, an electrical generator, and at least one supercapacitor, where an electronic control unit decides when to connect the supercapacitor to high-power devices based on how charged the capacitor is and how hot the device has gotten. What's protected here is specifically the architecture of using that supercapacitor as a power-delivery buffer and the logic that governs when it kicks in.
Why it matters
In the early 1990s, supercapacitors were an emerging technology, and this patent staked out a key use case in automotive electrical systems. Cars need massive instantaneous power for engine starting and other functions, and traditional batteries deliver that power inefficiently. By adding a supercapacitor to the mix, automakers could reduce strain on the main battery, extend battery life, and make electrical systems more reliable—especially in cold weather when batteries struggle most.
Real-world use
When you turn your key to crank a 1990s car engine, the supercapacitor in this system provides that massive initial surge of current to the starter motor, protecting your battery from the worst of the stress.
Original USPTO abstract
The system includes at least one auxiliary electrical user device which, in order to be activated, needs a high power for a short period of time, a rechargeable battery, an electrical generator for recharging the battery and at least one supercapacitor for storing enough energy to activate the user device The connection of the supercapacitor to the user device is controlled by an electronic unit in dependence on the charge state of the supercapacitor and the temperature of the user device.
Patent details
- Publication number
- US 5,260,637
- Filing date
- 1992-08-07
- Grant date
- 1993-11-09
- Assignee
- MAGNETI MARELLI S.p.A.
- Inventor(s)
- PIZZI; PIETRO
- CPC class
- H02J7/1423
Want to file your own patent?
If you're dreaming up the next breakthrough in automotive power systems, scan your idea with our free patentability checker to see what terrain is already staked out.
Free patentability scan