Super Capacitor Battery Hybrid

[brokencase]

Pretty interesting...
https://www.youtube.com/watch?v=gzaLF5tFf88

..and
https://www.temu.com/2-7v500f-super-far ... 00763.html

I'm thinking just having these across a normal battery would extend the life of the battery and would also permit parking the car without a battery tender for longer periods of time.

[DPDISXR4Ti]

Hmmm, interesting.... So you're thinking not so much a battery replacement but built-in battery-tender?

I see there's a bunch of other videos I could watch if I wanted to spend a couple hours getting smarter.

[Ed Lijewski]

Using regularly a good brand battery maintainer is far preferable as they have desulfating actions which will prolong battery life as well as enable functioning close to spec levels.

YMMV

[brokencase]

I'm going to try to explain to you how these can extend the time that the car can sit without a maintainer.

The capacitors charge up very quickly and they can dump a large amount of current. But they have limited capacity. By themselves they could only crank the engine maybe 2-3 times before they are depleted.

With a set of these caps in parallel with the battery, the battery never has to dump a lot of current to the starter. The caps do that. So the battery is less stressed. This will extend the life-span of the battery.

Now, one point to make is the property of the large current dump they can provide. If you install these properly (with good cabling) you will notice that the starter will feel much more zippy and stronger as a result of the large current dump that the caps can provide. This effect occurs even if the battery and caps are sitting at 11 volts after the car has been sitting a long while.

This is probably the hard part for you to understand, that is, a car battery sitting at 11 volts will have a hard time cranking the engine, but a set of super capacitors sitting at 11 volts will readily crank the engine.

This is because a battery sitting at 11 volts can't deliver much current. But the super capacitors can still provide a huge surge of current even at 11 volts.

[andyofcolumbusmerkur]

Those Maxwell capacitors are really nice high quality units. I see them used a lot in hospital lighting (in case power goes out) instead of the old mini battery pack. Big improvement over those lead acid ones. I wouldn't trust those cheapie versions in the link above that are $2.98 each listed as super capacitor gw series. At least not for anything remotely important. The cheapest I see the Maxwells are $20 each if you buy them in bulk. I also don't see the point in what that guy has in his CRV. After he spent 12 bucks for a little lead acid battery, 12 bucks for a balancing board, 120 for the Maxwells, and a few dollars for things like the container, bolts, and wiring he could have gotten the correct battery. I guess he just wants to be different. It's really no different (less the modern capacitor) than old school car audio setups that had the stiffening capacitor between the battery and the amplifier. The only thing that capacitor did was support more capacitors inside the amp and improve bass. They were not known for extending the life of the battery or helping maintain the battery.

[brokencase]

I agree the link to the super cap I posted earlier looks marginal, mainly because the small size of the leads.

I see there are sellers offering completed units with the balance boards up on ebay that go anywhere from $40 - $70.
But these are only 83F

Pre-assembled Maxell units are pretty pricey $290. They are on Amazon. There is a youtube video where the guy looks like he is using a similar cap to the Maxell that he got for a bargain somewhere.

[Ed Lijewski]

Brokencase wrote

Now, one point to make is the property of the large current dump they can provide. If you install these properly (with good cabling) you will notice that the starter will feel much more zippy and stronger as a result of the large current dump that the caps can provide. This effect occurs even if the battery and caps are sitting at 11 volts after the car has been sitting a long while.

This is probably the hard part for you to understand, that is, a car battery sitting at 11 volts will have a hard time cranking the engine, but a set of super capacitors sitting at 11 volts will readily crank the engine.

This is because a battery sitting at 11 volts can't deliver much current. But the super capacitors can still provide a huge surge of current even at 11 volts

I understood all that from before your explanation.

Listening to the Honda starter working, that crank speed sound is generically typical for Hondas of that vintage. The OP, and you, suggest it is or would be cranking "smarter"...but it didn't. On two starts. My battery maintainer-ed cars never have to crank more than a starter motor rev or two, but they twist the starter motor with assurance that if the engine didn't fire smartly there is a lot of confident oomph in reserve.

I'd rethink this if an install of capacitors audibly impressed starter motor performance.

YMMV

[brokencase]

I'd rethink this if an install of capacitors audibly impressed starter motor performance.

YMMV

It's not going to hurt the starter Ed.

[Ed Lijewski]

Nothing I wrote or implied even remotely suggested that.

YMMV

[brokencase]

Andy.. Here's an idea for a low budget approach...

Get a balance board...$13
https://www.amazon.com/ultracapacitor-s ... B01AM08OE6

And then 6 sets of 5 of the smaller caps I indicated earlier @ $13.48 ea,
https://www.temu.com/2-7v-500f-35-60mm- ... 00271.html

Wire each set in parallel and then solder (with big leads) to the balance board in series.

That gets us to a total of 16V @ 416F for just under $100. Just a bit shy of the 500F Maxell setup.

Allowing space for a box, wires, and the balance board - final package size would be around 185mm x 220mm x 75mm (7.28" x 8.6" x 2.9")

Spec sheet or the aforementioned caps...
http://www.samwha.com/electric/product/list_pdf1/db.pdf

Looks like each cap can discharge up to 25 amps.

[brokencase]

Nothing I wrote or implied even remotely suggested that.

YMMV

Then please explain what the you meant when you said "I'd rethink this if an install of capacitors audibly impressed starter motor performance"

[Ed Lijewski]

Capacitors store energy potential or voltage. Those big ass ones in the video audio don't seem to produce a faster starter twist than regular batteries in similar-size Honda vehicles. Listen to the starter crank; it's not anemic for sure but it doesn't "impress" aurally as beefier than what can be heard around a shopping mall from standard Honda batteried vehicles.

Maybe the caps putative output boost through the starter can be measured technically. Can we show that?

YMMV

[andyofcolumbusmerkur]

I've put the "big 3" or "big 4" ground wires on late model vehicles and it seems to make a difference in starting. That's just me listening to the before and after, I guess I was audibly impressed. The manufactures use the minimum amount of copper they can to save money. I would think that guy's CRV will always start kinda weak without some bigger wires.

[brokencase]

Even a fully charged battery will drop in voltage and current output as you crank the starter.

The super caps will drop in voltage as their charge depletes during the starting cycle but they will still provide the ample current. Naturally with the caps in parallel with the battery the situation is even more ideal as the battery will feed the caps as they drop.

No doubt in my mind that the car will start more readily with the super caps in place.

Andy is right about the using correctly gauged wires and keeping lengths as short as possible. Reminds me to check the condition of the cable going down to the starter on my Scorpio. Maybe near time to replace/upgrade it.

[Ed Lijewski]

Brokencase wrote

Reminds me to check the condition of the cable going down to the starter on my Scorpio. Maybe near time to replace/upgrade it.

.

I intended to install new battery cables on my '88 a couple years ago. But, the bolt holding the negative cable to the bell housing I judged not possible to access. So I ran a new negative cable to an engine bolt not far from the water pump, the easiest large dimension bolt I could access that wasn't for the exhaust manifold which I didn't want to mess with. Cable length was similar to the OE mount. No issues. I didn't change the starter cable (yet).

YMMV