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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

#161

Post by balls187 »

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,…

> (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)

I have a 2003 VW GTi. Had the battery replaced for the first time late last year. The AAA Tech was surprised that I had over 10 years of use with the stock battery.

Still, this product does seem interesting.

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

#162

Post by fredkbloggs »

atourgates wrote: post #131
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,…

If you look at this purely from the standpoint of the benefit to a consumer, it doesn't seem like a great deal. You gain: * Auto-shutoff when your battery gets too low. * Possibly some increased lifespan * ~34lbs in weight reduction, which might deliver a small performance increase. You lose: * 78% of your battery capacity * $20-$150 on the purchase price of the battery Personally, I don't like the idea of paying mor…

Suppose they did offer a 7-year warranty, with strong language. Would you really expect Ohm to be around in 7 years? If they want people to take a warranty seriously, it needs to be backed by at least an A-rated insurer, not whoever is funding these guys.

There's also the problem that they apparently offer only a single size/form factor (which is roughly equivalent to 34, 34/78, 75/25, or 35), and that for many applications this device does not offer enough starting power. Never mind reserve capacity. But even if this size is appropriate to your car, there are other reasons to be skeptical.

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

#163

Post by OopsCriticality »

blueintegral wrote: post #50
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'…

> that still leaves 24 million pounds of lead each year from car batteries that don't get recycled

Is that actually a lot? Similar statements are made with respect to nuclear waste, but frankly, I've regarded these statements in units of mass as deliberately misleading due to nuclear waste (or lead in this case) to be uniquely dense relative to what we are accustomed to dealing with on a daily basis.

Siri, via Wolfram Alpha, says that 24 million pounds of lead is about 33,900-ft3, or a cube of 32-ft a side. If correct, that doesn't feel like a lot considering this is framed as a the global lead acid car battery recycling waste.

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

#165

Post by conjecTech »

sliverstorm wrote: post #115

One challenge in going after the enthusiast market is going to be, the enthusiast market already has options. Back when I drove a fast sporty little car, I got one of these: http://www.amazon.com/gp/product/B0002ILK6I $100, 4 pounds. Proven technology. I can buy it today. Half the cost, 60% more capacity, and 2/3 the weight of this "Ohm". Smaller too, from the looks of the "Ohm". I'm not trying to rag on you guys, bu…

There are other lightweight batteries out there, but they generally aren't suitable for daily use for one reason or another. The usual sacrifices are either lifetime or performance over temperature. The battery you linked is only warrantied for 2 years and likely wouldn't work south of freezing - not quite what you'd expect for the price tag. We think we can already beat them on value prop, but with a little bit more work, we think we'll be able to get them cheaper than other lightweight solutions and eventually price competitive with a normal lead-acid.

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

#166

Post by birdmanjeremy »

Kluny wrote: post #114
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,…

(7) This doesn't apply to all performance cars, but in track racing where you really need to save every possible ounce, it's common to take the battery out altogether after starting the car and run it off the alternator.

I've never seen anyone do this. We just run lightweight batteries and keep the car on a tender.

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

#167

Post by atourgates »

baudehlo wrote: post #150
atourgates wrote: post #131

Earlier quoted context omitted.

If you look at this purely from the standpoint of the benefit to a consumer, it doesn't seem like a great deal. You gain: * Auto-shutoff when your battery gets too low. * Possibly some increased lifespan * ~34lbs in weight reduction, which might deliver a small performance increase. You lose: * 78% of your battery capacity * $20-$150 on the purchase price of the battery Personally, I don't like the idea of paying mor…

When I bought my Civic Type-R it didn't even have an option for air conditioning due to the weight it added. For some types of car every pound (though they are called grams in the real world) counts. I suspect this will be popular in the lightweight performance car world.

For sure losing 30+lbs is a big deal in the high-performance automotive world, and Ohm's price premium is nothing compared to, say, replacing structural elements with carbon fiber etc.

But I don't think your average mass-market consumer is going to care much about 30lbs, or notice a difference in performance or handling if they did.

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

#168

Post by oppositelock »

conjecTech wrote: post #151
oppositelock wrote: post #118

Modern cars with keyless entry typically draw ~50mA@12V when "off", this power is used to power the receiver, keep ECU state for such things as learned fuel maps, blink the alarm-on indicator, etc. 45Ah capacity gets you a bit over a month to drain down the battery, while 10Ah gets you a bit over a week. This isn't good, you'd have to keep it on a battery tender if you're not driving the car for just a week. I can al…

Co-founder here: The capacity isn't set in stone. You might be right, if we need to increase it we can - or just offer a couple different options, but so far we haven't seen any issues and a number of our beta users are only using their cars once every few weeks. The capacity quoted on lead-acid is also a bit deceptive. There amount of current you can draw drops pretty heavily with state-of-charge. You might have tro…

I can speculate, though :)

You can periodically pulse the circuit at a low voltage and figure out the resistance, and if the voltage is low enough, you won't power anything up. When the ignition goes into the ON position, you've got a huge drop in resistance as fuel pump, and other necessary electronics get enabled. A sudden drop in resistance is a good signal that you should turn the power back on. This will not work with some more recent electronic systems, but should work great for most mechanical ones. Pretty sure you haven't solved things like the interaction with a BMW battery monitoring computer, for example, and those cars will probably reject your battery with some crazy error after a while.

It's good that you've got space for more reserve capacity, parasitic drag is getting higher as cars get more fancy. For example, radiator fans and turbo oil circulators can run for quite a while after the engine is off.

Your super capacitor design is elegant - you can charge the supercap off the battery slowly, even at low state of charge where its voltage would sag too low for the starter relay if you were directly using the battery.

I have a little car which I race and weight matters, so I've been using a ~12Ah LiFePO4 home-made battery for a while (A123 cells). This is a very durable little battery chemistry. No fancy super-caps, though, I just keep mine topped off and starting the car puts the battery cells close to their maximum discharge current.

I wish you guys the best of luck. Lead acids are pointless with modern battery technology.

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

#169

Post by blueintegral »

mycelium wrote: post #155
blueintegral wrote: post #147

Earlier quoted context omitted.

You should get a bit longer than just a month of disuse before it shuts itself off. Are there modern cars that don't even let you use the key to open the door? I know Tesla has the thing where the handle is flush with the door, but are other cars doing that too now?

I have a 2015 VW Golf that has no keyed entry, just the fob buttons.

Maybe it's hidden like this? https://www.youtube.com/watch?v=OECOoNYZXmk

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

#170

Post by dzhiurgis »

atourgates wrote: post #131
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,…

If you look at this purely from the standpoint of the benefit to a consumer, it doesn't seem like a great deal. You gain: * Auto-shutoff when your battery gets too low. * Possibly some increased lifespan * ~34lbs in weight reduction, which might deliver a small performance increase. You lose: * 78% of your battery capacity * $20-$150 on the purchase price of the battery Personally, I don't like the idea of paying mor…

I guess the pitch is that you do not need the extra battery capacity?

Are you sitting in parking lots listening music these days? That did sound cool when you were kid, but majority will never do that (or take their car camping).

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