The son of a friend of mine recently had a problem starting his car, a conventional gasoline-powered vehicle. When the key was turned, it made that slow grinding sound which usually means the battery is weak.
This 300 Instant/600 Peak Amp Jump Starter from Black+Decker is quite handy, and much safer and easier to use than long inter-car jumper cables.
Since he wasn’t in a rush, and since jump-starting from another car was impractical for various reasons, he headed over to a nearby store for one of those convenient boosters: you connect it to an AC line, charge the internal battery, then bring that battery (with integral cables) out to your car and connect it for a jump, see here. These units are actually pretty handy and easier to set up than a car-to-car jump using those long cables (assuming you can position the two cars), with a chance of misconnecting or shorting things if you aren’t careful (a battery-to-ground short makes a very impressive spark!). The $50 retail price is also reasonable, IMO.
Still, I was surprised when he called me from the store with a “simple” question, to make sure he was getting the right charger/booster: “is that battery 6, 12 or 24 V?” he asked. At first I thought this might be a trick or joke question, but he was serious. (Of course, the answer is 12 V.)
It turns out it wasn’t a trick question; he was serious. I assumed incorrectly that “everyone” knows a standard car battery has a 12-V rating (actually, 12.6 V nominal) and that knowledge is part of the common culture.
Looks like I assumed wrong. My gut reaction was “how could you NOT know that?” but then I gave it some more thought and reconsidered, and realized two things. First, this person is no technical dummy. He routinely sets up and gets different networks and systems connected, talking and even happy with each other; that’s often a real challenge when you are configuring systems from different vendors or apps. I’ve seen him do this and it is an impressive feat.
Second, today’s cars are basically hostile to average people poking around in them. There are so many sophisticated electronic modules, networks, functions, and features that you are diving into a jungle when you open the hood. Unless you have a good sense of what you are doing, there’s not much you can do; you are taking a big chance by going in and poking around. It seems like an unintended and unforeseen consequence of the complexity of today’s cars is to discourage the average person from doing anything on them, even basic maintenance. (A cynic might say this is not at all unintended or unforeseeable, of course). Even the humble, basic car battery is now part of a complicated power-management subsystem which monitors voltage, current flow, cycles, and much more.
The situation is analogous to the dilemma we have with electronics and experimenters. On one side, we urge students to explore, build circuits, and do more than just sit at a keyboard playing with apps and thinking that keyboarding is all there is to engineering. But the reality is that is very hard to build real circuits with today’s ICs and passive components due to their tiny pads and dense interconnects. Building, loading, and soldering a prototype is a real challenge and whole “maker” subculture has found ways to do it with magnifying glasses, tweezers, and modified toasters.
Further, if the beginner does have the patience and skill/luck to build that board, it is still very hard to “play with circuit” as part of the project—it’s hard to probe voltages and currents, or change components to try something out. While there are some ways to minimize the problem by using leaded discrete components, through-hoIe ICs (yes, you can still get some in DIPs), and various prototyping boars, you are very restricted in what you can build.
The more I thought about him not knowing that the car has a 12-V battery, the more I concluded that this is not a matter of technical ignorance in itself, but rather an issue of his technical insight being naturally redirected to where he can actually do something. Maybe it’s the new “normal” that we, as engineers, had better get used to?
What’s your view on increased product complexity diminishing the need or ability to underhand basics such as a car battery?
Powering the autonomous car
New cars making tapping battery power tough
Will cars get on the 48V bus?