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Ohm (YC S15) is a smarter, lighter car battery that works with your existing car

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Re: Ohm (YC S15) is a smarter, lighter car battery that works with your existing car

#41

Post by morcheeba »

sandworm101 wrote: post #27

(1) Those nasty things inside car batteries are easily recycled and in fact are recycled more often than not (like 95%+) (2) Car batteries do not last only 3-4 years as per the OP. Car batteries can last decades. There are many variables, but the car in my battery is far older than 4 years. (lol) (3) Replacing an easily-recyclable product with a less-recyclable one is no step forwards. (4) XX addressed by OP comment,…

I don't get your (4). It's a capacitor + lithium battery. It's got to be nominally 12 volts, or else it wouldn't work in a car. Capacitors only charge to the voltage you apply -- in this case, 12v. I'm not sure if you mean voltage by "beyond that", but fire risk isn't really correlated with voltage - more with chemistry, energy, and fusing.

As for (5), they clearly care about cost.

Re: Ohm (YC S15) is a smarter, lighter car battery that works with your existing car

#42

Post by nacs »

Cshelton wrote: post #5

So yesterday Audi/Porsche/VW announced a new v6 engine that will be used in variations across all their vehicles. Further down the line, they said that engine would include an electric drive component as well, incorporating a battery, effectively making all their cars "hybrids". This seems to be the trend, see racing tech (Formula 1, WEC, etc.). We will probably see this in all new consumer cars sometime soon. Once e…

> At your price point, performance/luxury cars seem to be your only market,

I'm not sure even that will be a market they can cater to as newer performance/luxury cars have a massive amount of electronics and computers inside that put a heavy continuous drain on the battery (and continue to drain even when the car isn't running).

Considering this new battery can't even hold the amount of power that a normal car battery can, I don't see it being used in high-draw luxury vehicles.

Re: Ohm (YC S15) is a smarter, lighter car battery that works with your existing car

#43

Post by conjecTech »

eggoa wrote: post #4
blueintegral wrote: post #2

Hey everyone! I'm Hunter, one of the cofounders of Ohm. Let me know if I can answer any questions.

Will this work when its -30F?

The capacitors are fairly immune to temperature variation since they don't store energy using a chemical reaction, and we can also dynamically adjust the standing voltage of the caps to increase power in cold conditions.

We believe so, but don't want to say it until we can verify for sure. Our temp chamber unfortunately has trouble pushing anything south of -20F and it's a bit hard to find weather that cold in August.

Re: Ohm (YC S15) is a smarter, lighter car battery that works with your existing car

#44

Post by Eiriksmal »

sandworm101 wrote: post #27

(1) Those nasty things inside car batteries are easily recycled and in fact are recycled more often than not (like 95%+) (2) Car batteries do not last only 3-4 years as per the OP. Car batteries can last decades. There are many variables, but the car in my battery is far older than 4 years. (lol) (3) Replacing an easily-recyclable product with a less-recyclable one is no step forwards. (4) XX addressed by OP comment,…

While I agree with points 1 and 2, I have a beef with point 5. Car manufacturers do whatever they can to shave costs, all over the car, all the time. Batteries are needlessly heavy because they are manufactured with the cheapest-possible components using the cheapest-possible technologies. They do put in a best-guess size to keep the median consumer masses happy, whether they drive the car once a month in Death Valley or six times a day in Duluth.

You can buy lighter-weight, lower-capacity batteries to use in competitions where weight matters, or higher-technology batteries for use in angles where lead-acid will give up the ghost. Batteries are frequently moved by tuners to places where their weight has less of an affect on the car's suspension.

Re: Ohm (YC S15) is a smarter, lighter car battery that works with your existing car

#46

Post by function_seven »

carbocation wrote: post #33
bluehawk wrote: post #30

Earlier quoted context omitted.

In Arizona, you're lucky if it lasts for 2 years. Batteries don't like being in 120 degree heat all day or something.

I've lived in both Cambridge, MA and Scottsdale, AZ, and my batteries routinely die in under 2 years. I think it's mostly a function of my (infrequent) driving habits.

> I think it's mostly a function of my (infrequent) driving habits.

Yup. I bought a Battery Tender[1] for my infrequently-used vehicles and now the batteries last indefinitely[2]

[1] http://amzn.com/B000CITK8S

[2] :) Based on the fact that I haven't had to replace them yet after 5 years.

Re: Ohm (YC S15) is a smarter, lighter car battery that works with your existing car

#47

Post by sandworm101 »

morcheeba wrote: post #41
sandworm101 wrote: post #27

(1) Those nasty things inside car batteries are easily recycled and in fact are recycled more often than not (like 95%+) (2) Car batteries do not last only 3-4 years as per the OP. Car batteries can last decades. There are many variables, but the car in my battery is far older than 4 years. (lol) (3) Replacing an easily-recyclable product with a less-recyclable one is no step forwards. (4) XX addressed by OP comment,…

I don't get your (4). It's a capacitor + lithium battery. It's got to be nominally 12 volts, or else it wouldn't work in a car. Capacitors only charge to the voltage you apply -- in this case, 12v. I'm not sure if you mean voltage by "beyond that", but fire risk isn't really correlated with voltage - more with chemistry, energy, and fusing. As for (5), they clearly care about cost.

I was thinking about the internals. They might have components with higher potentials that are then regulated down to 12v. In a crash, those could be a source of high-voltage shorts that might be a source of ignition.

Re: Ohm (YC S15) is a smarter, lighter car battery that works with your existing car

#48

Post by Eiriksmal »

sokoloff wrote: post #28

> Oh, and its lifespan (7 years) is about twice that of a lead-acid battery (3-4 years). I live in Cambridge, MA (so we get winters) and I can't remember the last time I've had a regularly driven car's battery fail in under 7 years.

I've never figured out why some batteries last and others don't. My '05 6MT V6 sedan still had its OEM battery when the starter finally refused to turn over in 2013. My wife's '07 5AT I4 sedan just got its fourth battery this month. My car grew up in central Kentucky, hers spent its first 3 years in New England before also moving to ol' Kintuck.

Re: Ohm (YC S15) is a smarter, lighter car battery that works with your existing car

#49

Post by conjecTech »

sokoloff wrote: post #28

> Oh, and its lifespan (7 years) is about twice that of a lead-acid battery (3-4 years). I live in Cambridge, MA (so we get winters) and I can't remember the last time I've had a regularly driven car's battery fail in under 7 years.

I'm glad you've been so fortunate. There definitely is some variation. There are a lot of outliers on the other side too. The 3-4 year number is what most manufacturers themselves claim.

Re: Ohm (YC S15) is a smarter, lighter car battery that works with your existing car

#50

Post by blueintegral »

sandworm101 wrote: post #27

(1) Those nasty things inside car batteries are easily recycled and in fact are recycled more often than not (like 95%+) (2) Car batteries do not last only 3-4 years as per the OP. Car batteries can last decades. There are many variables, but the car in my battery is far older than 4 years. (lol) (3) Replacing an easily-recyclable product with a less-recyclable one is no step forwards. (4) XX addressed by OP comment,…

You're right! Lead acid car batteries are one of the great recycling success stories. What's interesting is that the volume of lead acid car batteries in the world is so high, that even at that high recycling rate, that still leaves 24 million pounds of lead each year from car batteries that don't get recycled. There's also been some problems recently with lead recycling plants contaminating the environment [1].

You're also right that it's more complicated to recycle lead than lithium batteries, but a recycling process does exist, and it's getting better thanks to the proliferation of lithium batteries in electric cars.

It's actually got 6 capacitors in series (2.7V each). We don't charge them all the way up to 2.7V, so it's normally at about 13V on the terminals. We are super paranoid about safety. The EDLC caps we picked aren't a fire risk, since it's just carbon and a few mL of electrolyte. You're probably thinking of what electrolytic caps do when you reverse bias them, but EDLC caps are much nicer. The worst they'll do is vent the electrolyte, not explode. LiFePO4 batteries are also really stable and are used in electric vehicles all the time.

[1]: http://losangeles.cbslocal.com/2015/07/08/lead-contamination...

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