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Can this battery be used to jump another (traditional or Ohm) battery when required?
Usually, when jumping another car, you are supposed to leave the car running, getting power off the alternator rather than the battery.
Can this battery be used to jump another (traditional or Ohm) battery when required?
> 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.
In Arizona, you're lucky if it lasts for 2 years. Batteries don't like being in 120 degree heat all day or something.
Such small capacity would work only for perfectly starting engine. Any issues and you're out of capacity. Cranking an engine requires hundreds of Amperes, like 500-800A. Thus each 10s of cranking burns 1.5-2.5Ah.
The CCA rating of a car battery is the current the cold battery can produce during 30s. 10Ah LiPo at 30C would mean maximum 300 CCA - i don't think it would satisfy any official reqs for any passenger car around. The super capacitor produces higher current, yet for much shorter bursts. Thus again only easy starting engines on smaller cars.
Earlier quoted context omitted.
Will this work when its -30F?
>> Rated for -30°C to +50°C [1] -22F ~ -30C [1] http://www.getohm.com/
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 Is this really true? It sounded from the article like they're only about $50 more than a typical battery, unless I missed something. I could see some people with normal cars shelling out $50 for the longer life and features to avoid a dead battery, even if the reduced weight doesn't matter much to them.
Most people will take their car to a repair shop when they have problems with their battery and will take whatever battery the tech/shop suggests (as long as its in their price range).
Unless this company starts pitching their batteries really well to these repair shops, they're not going to see much business.
(1) Perhaps the design flaw is in the children.
Hey everyone! I'm Hunter, one of the cofounders of Ohm. Let me know if I can answer any questions.
> if it’s ever about to reach the point that it’ll no longer be able to start your car, it’ll just turn itself off. Your lights will fade out and the radio will go quiet — but once you turn the key, everything will spring right back to life, no jump start required. How does that work? If the battery stops providing current to prevent itself from being fully drained, you're not going to have power to the car's compute…
It will know when the internal batteries are running low (the internal charge/discharge monitor IC doing battery "gas gauge" measuring). It'll maintain a reserve of a few crank's worth of energy, and trigger shutdown before that's exhausted.
It can also tell if the engine is running, because the alternator will be, and charging it. It can also monitor the active discharge current.
If the battery is low and there's a small but fairly constant discharge, it's probably lights/radio, and a timeout of an hour might be reasonable.
It could then either cut power completely, or regulate discharge current to a couple of milliamps or something, just enough to sense teh spike when the starter motor is switched in. At that point, it switches in the supercap or goes back to full power 12v mode, and the starter gets cranked.
The only downside I can see is that fully isolating the battery may have side effects that upset the ECU, radio or immobiliser system (I recall our radio would go into 'presumed stolen' mode if fully disconnected and require a PIN to work properly, I have no idea if/how that happens in modern cars though)
A "dead" lead-acid battery often isn't dead enough for that to happen, just htat it can't supply the ~200A that the starter requires to crank.
Lead acid is traditionally very forgiving with regards to temperature. How does the electrical performance of your battery vary with temperature, especially at extremely cold (-40C) and extremely hot (80C) conditions?
How does it handle a car that's iffy on starting? It's probably not hard to get something that'll crank a starter for a few seconds. But what happens if it needs to crank for 60 seconds over a 90 second window? I've got a 2006 Forester with a manual. I'll occasionally stall it backing out of a parking spot, so I'll have to start it again. For some reason it's much more difficult to start in between cold and warmed up…