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He also went on to state that you could use their lightweight Li battery in a daily driver, "..as long as it is not used in cold weather.", without defining how cold that weather really was.

 

Li technology for automotive use is a relatively new and evolving technology, and a very interesting one at that.  But like most emerging tech, it still has a bit of the "wild west" in it that will shake out over time, but using "equivalencies" that seem purposely deceptive to sell the products is not helping their case any.

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Ya, I think in general there is a lot of misinformation and a lack of understanding about batteries in general -- before you even start getting into the type like LI, lead acid, AGM, gel, etc.  When I went to Advanced Auto Parts (AAP) over the summer to check on buying an Optima the "battery guy" didn't even know what an AGM battery was (yikes).

 

Also when I bought the Optima I saw a lot of reviews that said Optima moved from the USA to Mexico, shame on them, and the quality is trash now.  But I looked into it quite a bit and I think that's just isolationist/patriotic/racist sentiment because I read a lot of the complaints about this battery and it was stuff like they were mad it's not made in the USA anymore or something like the consumer mixing up "state of charge" and "aging".  In other words they would complain something like "I got this expensive trash Optima battery brand new today and hooked it up and it only has 70% life left, what a piece of junk!!!"  When you look closer you can see that what they don't realize is they are actually looking at the state of charge, not aging.  And it's very typical for a new battery not to be fully charged to 100%.  In other words they just didn't know what they were doing but left a bad review and 1 star as a result.  Lots of things like this.  To me the more realistic question is how many years will I really get out of it but based on empirical evidence I would expect at least 10 and maybe as much as 15 years (remember the over/under on my Q5's OE Varta AGM was probably going to be around 8 or 9 years if I was an oddsmaker).

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Let me try to get this thread back to its original intent: I bought a new interesting toy for my car and am sharing my experience with the other members. I have learned a lot in this forum, much more than I have given back and occasionally I try to share a bit of my knowledge and experiences here and in other forums I participate in. For quite a few years, I have been also giving back in financial support to help keeping the place up and running. 

 

Let me also make a disclaimer: I don't work for or in any way am affiliated or have any interest in battery manufacturers, resellers, car dealers, workshops, race teams, whatever. I won't also go on to claim high levels of technical knowledge or authority on anything and certainly this is not the place to do so. You can look me up in Linkedin, that's where I believe to be the place to ruffle professional peacock feathers to try and get attention to gain some professional and hopefully, financial advantage. If you find me there, you can have an idea of my level of professional technical knowledge, if any.

 

I come to places like this to have fun, proudly showing my toys and enjoying somebody else's as well as looking for help in solving technical problems and giving back when I can.

 

I don't understand why this is happening in this thread, an insistence on demeaning a toy, copy/pasting specifications of a different battery to try and make a point against another battery because they look the same? What is this?

 

Further, claiming that lithium batteries are no good to start a street car because one race team in one competition starts their cars with off-board AGM batteries and then switch to on-board lithium, thereby lithium are no good for street cars, is laughable. What do racing conditions and hardware have to do with street cars? Guess what, many race teams in many competitions change Michelin tires twice per race, thereby Michelin tires are no good.

 

In these few days of use, this battery has been performing beautifully in the car, starting it without hesitation or hiccup and showing no signs of lack of power under any circumstance.

 

If you have seen cars with their engines running and having issues with headlights dimming when the stereo or AC was running, then I suggest to check the electrical system in other elements other than the battery since that would be unrelated.

 

Let me very clear, again: I'm not claiming any kind of superiority of the battery I bought over any other kind. I don't care.

 

I'll be reporting back on this thread on my experience over time, so that others may have an idea on how good or bad this particular battery is for this particular application: Porsche 996 Turbo living in a temperate climate and sleeping every night in a garage where temperature never goes under 18ºC.

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The Li battery business is suffering from a similar problem that the light bulb business had when switch from incandescent to LED.  People had long associated bulb wattage with light level output, even thought wattage was actually measure of how much energy the bulb consumed and heat it generates rather than light output levels.  So when consumers saw that an LED replacement for a 7 watt night light bulb only used 1.3 watts of power, their immediate assumption was that the LED would be much dimmer in light output than the incandescent bulb, which was anything but correct; and that stalled acceptance of the LED replacements for a period of time.  Fortunately, there was another widely accepted scientific standard for light output: Lumens  So when comparing replacement bulbs, consumers discovered that a 25 watt incandescent bulb and a 3 watt LED bulb both produced 130 lumen, meaning they were equally as bright, and that a 40 watt incandescent had the same lumens as a 5 watt LED, consumers now had a sound and reproduceable way of relating the product specs to their needs.

 

Unfortunately, no such relatable second scientific measure currently exists for comparing conventional batteries to Li based units amperage performance under the same conditions.  As as shown by the comments I quoted above, even within Li battery manufacturers there is no mutually agreed upon "equivalency" standards that either the BCI or SAE could buy into, much less help consumers make purchasing decisions.

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34 minutes ago, laalves said:

Let me try to get this thread back to its original intent: I bought a new interesting toy for my car and am sharing my experience with the other members. I have learned a lot in this forum, much more than I have given back and occasionally I try to share a bit of my knowledge and experiences here and in other forums I participate in. For quite a few years, I have been also giving back in financial support to help keeping the place up and running. 

 

Let me also make a disclaimer: I don't work for or in any way am affiliated or have any interest in battery manufacturers, resellers, car dealers, workshops, race teams, whatever. I won't also go on to claim high levels of technical knowledge or authority on anything and certainly this is not the place to do so. You can look me up in Linkedin, that's where I believe to be the place to ruffle professional peacock feathers to try and get attention to gain some professional and hopefully, financial advantage. If you find me there, you can have an idea of my level of professional technical knowledge, if any.

 

I come to places like this to have fun, proudly showing my toys and enjoying somebody else's as well as looking for help in solving technical problems and giving back when I can.

 

I don't understand why this is happening in this thread, an insistence on demeaning a toy, copy/pasting specifications of a different battery to try and make a point against another battery because they look the same? What is this?

 

Further, claiming that lithium batteries are no good to start a street car because one race team in one competition starts their cars with off-board AGM batteries and then switch to on-board lithium, thereby lithium are no good for street cars, is laughable. What do racing conditions and hardware have to do with street cars? Guess what, many race teams in many competitions change Michelin tires twice per race, thereby Michelin tires are no good.

 

In these few days of use, this battery has been performing beautifully in the car, starting it without hesitation or hiccup and showing no signs of lack of power under any circumstance.

 

If you have seen cars with their engines running and having issues with headlights dimming when the stereo or AC was running, then I suggest to check the electrical system in other elements other than the battery since that would be unrelated.

 

Let me very clear, again: I'm not claiming any kind of superiority of the battery I bought over any other kind. I don't care.

 

I'll be reporting back on this thread on my experience over time, so that others may have an idea on how good or bad this particular battery is for this particular application: Porsche 996 Turbo living in a temperate climate and sleeping every night in a garage where temperature never goes under 18ºC.

 

No one here is "demeaning" your postings.  Our intent is to help people with problems, and provide some educational context for all readers to consider when considering potential purchase decisions.

 

My comment on headlights dimming was a real world experience that has occurred more than once when customers with light weight Li batteries brought cars into the shop complaining of these problems. Subsequent testing showed their charging systems were performing completely within normal specs, but when the AC clicked on, or a strong base section hit the stereo system, the lights dimmed because the available reserve amperage capacity of the battery was not up to the conditions.  To demonstrate to the customer where the problem actually was, we put a brand new 800 CCA AGM battery in the car at no charge to the customer, with the agreement that they would return in a day or two to tell me what happened. In every case, they came back and said the problems had disappeared immediately and did not reoccur, and most purchased the battery we had installed for them.  Those that did not purchase the replacement battery at least left the shop understanding why the problem happened, and in every case remained a good client with a better understanding of their cars.

 

As for race cars, as another poster mentioned above, they have relatively very low power draw when out on the track, so a light weight battery with enough current output to run the few electronics use is sufficient.  But when the car pulls into the pits and has to shut off for refueling or tires as required by the sanctioning body, the light weight Li battery was not up to spinning over the hot, high compression engine under restart, so they would plug in a high output conventional battery to get it going again. Under those conditions, reserve amperage capacity momentarily become critical, and demonstrates the limitations of lightweight batteries.

 

At the end of the day, it is your car and your money.  The battery you installed may serve you needs well in the climate you reside it, but for someone living in northern Montana, where the snow is already on the ground and daytime high temps are in the mid teens Fahrenheit, it might not be such a good idea.  So context becomes important.

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Any recent car has an electrical system designed to not let that happen, if working per spec. The alternator produces enough energy to all the consumers in the car at all regimes. The 996TT has a nominal 150A alternator which provides max current, if needed, already at idle. AFAIR, those Bosch alts max at 1300rpm (alt rpm, not engine). It's just 2.8HP stolen from the engine anyway. If a consumer requests more current, the regulator ensures that it is provided.

 

What that behaviour tells is that the alternator and/or regulator were not to spec. From the moment you turn the engine on, the battery is not doing anything other than getting recharged from the starting effort. As one throttles up and down, the battery will serve as a sink that will smooth out voltage peaks, shielding the electronics from those peaks. Other than that, start the engine and take the battery out if you want to, engine will continue to turn happily, lights will remain on, music will continue to sound. Possibly fry the ECU as well since voltage peaks will not be filtered.

 

If those cars needed a battery to have basic, stock consumers working properly at idle, the alternator and/or regulator was shot (or there is a severe current transmission issue) and those new batteries became very old very quickly because they wouldn't get properly charged.

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28 minutes ago, laalves said:

Any recent car has an electrical system designed to not let that happen, if working per spec. The alternator produces enough energy to all the consumers in the car at all regimes. The 996TT has a nominal 150A alternator which provides max current, if needed, already at idle. AFAIR, those Bosch alts max at 1300rpm (alt rpm, not engine). It's just 2.8HP stolen from the engine anyway. If a consumer requests more current, the regulator ensures that it is provided.

 

What that behaviour tells is that the alternator and/or regulator were not to spec. From the moment you turn the engine on, the battery is not doing anything other than getting recharged from the starting effort. As one throttles up and down, the battery will serve as a sink that will smooth out voltage peaks, shielding the electronics from those peaks. Other than that, start the engine and take the battery out if you want to, engine will continue to turn happily, lights will remain on, music will continue to sound. Possibly fry the ECU as well since voltage peaks will not be filtered.

 

If those cars needed a battery to have basic, stock consumers working properly at idle, the alternator and/or regulator was shot (or there is a severe current transmission issue) and those new batteries became very old very quickly because they wouldn't get properly charged.

 

Sorry, but no, voltage and amperage out put of the alternators in question were dead on rated spec for the vehicle involved, and remained so under load; the weak spot was the amperage reserve, not the voltage reserve, in the battery during periods of high demand. 😉

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Sorry, that cannot happen in a modern, well functioning car. If it were, cars would not idle for long. Battery would be depleted and there would not be enough current to keep the car running. If they had big aftermarket amplifiers then that surely can happen. Stock consumers, that doesn't happen. That's why the bassbombing crews install bigger alternators, bigger batteries and capacitors to increase available current reserve to feed the monster subs. To have all that working properly, it may even require an ECU remap to compensate for increased idle torque due to the bigger alternators. That's what they do in police cars.

 

As the loads increase, the regulator compensates the voltage drop by letting more current flow through the exciter which in turn increases the magnetic force generated by the field, hence causes more drag on the engine and the ECU injects more fuel to compensate for the added necessary torque. Engine RPM changes little, output torque increases what is required to put out more current.

 

There is no way to properly test an alternator in the car, only in a bench, there's no way to cycle it to max load and back in the car.

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Family in new car, dead winter, night, snow storm. Car goes off-road and gets stuck in snow in the middle of nowhere. Car is idling, heater at max, radio playing, headlights on, window defrosters on. Alternator not putting out enough current and needs to draw current from the battery to keep everything running, "as designed". After a couple of hours, battery dies and the engine follows suit. Family dies. Manufacturer says: "Tough luck, car was working as designed".

 

Doesn't happen in a car working to spec.

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1 hour ago, laalves said:

There is no way to properly test an alternator in the car, only in a bench, there's no way to cycle it to max load and back in the car.

 

I would not bet on that, modern load testing equipment can load test the alternator in the car, and can even test the diodes' with it in there.  Units can be pricey, often $4K (US) or more, but will test the entire system.

 

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21 minutes ago, laalves said:

Family in new car, dead winter, night, snow storm. Car goes off-road and gets stuck in snow in the middle of nowhere. Car is idling, heater at max, radio playing, headlights on, window defrosters on. Alternator not putting out enough current and needs to draw current from the battery to keep everything running, "as designed". After a couple of hours, battery dies and the engine follows suit. Family dies. Manufacturer says: "Tough luck, car was working as designed".

 

Doesn't happen in a car working to spec.

 

Doesn't happen because the car the family is in had a 700-800CCA or so battery with loads of current reserve.  But with a lightweight battery with limited current reserves (read amperage), it would definitely be a possibility given enough time. 

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Sorry, but i have to insist. Cars are not designed that way, they do not draw from the battery at idle, batteries would not last through a single winter of urban traffic jams as they would never be recharged after they started the engine. There's no point in continuing this discussion.

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