Anyone else wonder why we need a 50lb lead starter battery?

[Chawumba]

Seems like we already have installed in our vehicles a decent capacity lithium battery for the hybrid system. What is the point it lugging around an extra lead/glass mat battery mounted high in the front of the car? Seems so pointless.

On other vehicles I've owned, I've installed Antigravity brand lithium batteries to replace the lead acid battery and save about 80% of the weight, but in our car it seems like we shouldn't need a starter battery at all.

BTW, anyone wanting to use an RS-30 in a gen 2 nsx, I tried it, it doesn't work. Besides the challenge of fitting it in the insulating/cooling box, they don't work because Acura's smart battery charging system periodically runs the battery below 12.4 volts, which switches the antigravity battery to off, which necessitates opening the front hood to reset it. Not useful.

 

[Bricks and Bio]

Welcome to the board
Doesn't the car require a consistently available source of power (if the hybrid batteries were exhausted and you wanted to start the car)
My Infiniti Q50 hybrid also has a traditional battery

 

[Olyar15]

There are a lot of electronics in a car that is still designed for 12V. Hybrid batteries are some crazy voltage, which will fry the 12V electronics. BTW, the 12V battery doesn't start the car. There is no traditional starter motor, it uses the rear electric motor to start the engine. So technically, the hybrid battery does start the car. You just need the 12V battery to power the important stuff like the ECU.

 

[jkoyasak]

Even our Tesla has a 12V battery and the car is bricked if it dies...

 

[tucsonsx]

In EV land " bricked " means the HV battery is totally discharged ( just trying to save you the humiliation of using the term incorrectly on the TMC site ). In the case of a totally discharged 12V battery the car can be jumped to bring the HV battery back into service by using another battery or one of the LI jumper batteries now sold - I have a screw driver to remove the clips and an Anti-Gravity Micro-Start in my Tesla for this unlikely occurrence. The car gives you plenty of warning messages before the 12V is totally discharged so the incidence of this is really rare but, as we all know with machines, anything can happen.

 

[jkoyasak]

In EV land " bricked " means the HV battery is totally discharged ( just trying to save you the humiliation of using the term incorrectly on the TMC site ). In the case of a totally discharged 12V battery the car can be jumped to bring the HV battery back into service by using another battery or one of the LI jumper batteries now sold - I have a screw driver to remove the clips and an Anti-Gravity Micro-Start in my Tesla for this unlikely occurrence. The car gives you plenty of warning messages before the 12V is totally discharged so the incidence of this is really rare but, as we all know with machines, anything can happen.

Thanks for the correction - much appreciated !

 

[drmanny3]

Lets be clear if we are correcting people. Anti Gravity battery? Everything on this planet is impacted by gravity. The only thing that is not is Superman! What you really mean is that the battery can be placed in a variety of positions, even upside down and still function. Traditional 12 Volt lead acid batteries must be kept upright otherwise they will leak. Glass mat batteries also can be placed in a variety of positions. There are lead acid batteries that are sealed as well and can be placed upside down if necessary. Look at most alarm batteries. Anyway, chances are good that the car was designed with the 12 volt battery which I understand is glass mat based. Our cars have a significant weight distribution. So if you pull weight out of the front, that might impact the cars performance. Not a big deal for me as I don't track my car. In my 2001 NSX that was Comptech Supercharged I replaced the battery with a snowmobile 12 volt battery that was very light. It required a special battery minder as parasitic loads would consume the energy making a jump necessary. I liked the looks and it lasted for the three years that I used it. For the NC1 cars the battery is hidden from sight. I might be inclined to change it out if it was in sight. Having said that, it is a glass mat which is much more capable in a vibration prone environment. The glass mat batteries were often used early on in SUV applications as the vibration was killing traditional lead acid batteries.

 

[drmanny3]

Here is what the setup looked like that I had in my 2001http://uploads.tapatalk-cdn.com/20170420/a1eee348a874cea2b8ada1a7ef512e4f.jpg

 

[drmanny3]

Shorai LFX36L3-BS12 LFX Lithium Iron Light Weight High Performance Motorcycle Battery for Harleys and Large V-Twins - 36 Ah 12V 4.5 Lbs 540 CCA - LEFT NEGATIVE TERMINAL - 5 YR WARRANTY by Shorai Power BPD 5.0 out of 5 stars 2 ratings Price: $296.75 & FREE Shipping Note:Not eligible for Amazon Prime. Item is returnable in 30 days and restocking fee may apply https://images-na.ssl-images-amazon.com/images/I/91MWYVDlhpL._AC_SL1500_.jpg • It's Lighter, Smaller, More Powerful, Vibration Resistant, able to Hold a Charge Longer than a lead-acid battery AND it comes with a 5 Year Warranty. Need I say more? • Left Side Negative Terminal 12 Volt 4 Pound 8 Ounces 540 Cranking Amps 36 Ah (Pb Eq) Amp Hours • Excellent for everyday use in Harley & Other Large V-Twins (Please check compatibility at www.Shoraipower.com) Drop-in replacement for OEM batteries - Comes with plenty of adhesive backed foam padding. • Zero Sulfation for longer service life. Ultra Light - One fifth the weight of lead-acid batteries on average. Military Spec Carbon Composite Case. Holds a charge up to a year provided there are no "Parasitic Drains" (Accessories that draw power when the bike is off (Alarms, Clocks, ECUs, GPS, Heated Grips, etc). Faster cranking for better starts. Super-fast recharge rate. No explosive gasses during charge - No lead, no acid. • Comes with a NEW 5-Year Warranty! (check manufacturer's website for details - shoraipower.com) ***USE A SHORAI BRAND LITHIUM ION CHARGER TO AVOID DAMAGING THE BATTERY*** NOTE: Shorai Batteries require a charging system output of 13.1 Volts or higher at idle, and must not exceed 15.2 volts at maximum output.

 

[drmanny3]

Seems like we already have installed in our vehicles a decent capacity lithium battery for the hybrid system. What is the point it lugging around an extra lead/glass mat battery mounted high in the front of the car? Seems so pointless.On other vehicles I've owned, I've installed Antigravity brand lithium batteries to replace the lead acid battery and save about 80% of the weight, but in our car it seems like we shouldn't need a starter battery at all.BTW, anyone wanting to use an RS-30 in a gen 2 nsx, I tried it, it doesn't work. Besides the challenge of fitting it in the insulating/cooling box, they don't work because Acura's smart battery charging system periodically runs the battery below 12.4 volts, which switches the antigravity battery to off, which necessitates opening the front hood to reset it. Not useful.

Where did you find that Acura charges the battery at below 12.4 volts?

 

[tucsonsx]

Lets be clear if we are correcting people. Anti Gravity battery? Everything on this planet is impacted by gravity. The only thing that is not is Superman! What you really mean is that the battery can be placed in a variety of positions, even upside down and still function. Traditional 12 Volt lead acid batteries must be kept upright otherwise they will leak. Glass mat batteries also can be placed in a variety of positions. There are lead acid batteries that are sealed as well and can be placed upside down if necessary. Look at most alarm batteries. Anyway, chances are good that the car was designed with the 12 volt battery which I understand is glass mat based. Our cars have a significant weight distribution. So if you pull weight out of the front, that might impact the cars performance. Not a big deal for me as I don't track my car. In my 2001 NSX that was Comptech Supercharged I replaced the battery with a snowmobile 12 volt battery that was very light. It required a special battery minder as parasitic loads would consume the energy making a jump necessary. I liked the looks and it lasted for the three years that I used it. For the NC1 cars the battery is hidden from sight. I might be inclined to change it out if it was in sight. Having said that, it is a glass mat which is much more capable in a vibration prone environment. The glass mat batteries were often used early on in SUV applications as the vibration was killing traditional lead acid batteries.[/QUOTE

It is actually much simpler than all that - what I am referring to is the brand name AntiGravity and this product: www.antigravitybatteries.com/products/micro-starts/sport/ which I originally bought to use with my ICE cars: it is pretty handy - easy to carry and easy to use.

 

[Chawumba]

Where did you find that Acura charges the battery at below 12.4 volts?

Antigravity is a brand name of Lithium lightweight batteries that are often used to replace heavy lead acid car and motorcycle batteries. I bought one for my last ICE vehicle, was able to remove 48lbs from the car by switching, and the lithium battery has greater capacity, and last for more duty cycles. They have a line of batteries with a reserve feature - the battery shuts itself off if voltage drops below a predetermined lever (apparently 12.4v from an email I received). When I put their RS-30 model (which I borrowed from my F type, so I know it was working fine) in the NSX, about every 2nd drive the battery would shut itself off. Antigravity says that happens on cars with active battery management (some of which are designed to intentionally let the battery discharge a bit and then recharge fully).

I have now just tried the ATX-30-HD model, as it does not have the restart feature so won't shut itself off. I'll report back after a few weeks of use for those that are interested.

I'm of the belief that weight is the enemy of performance, and so the point of my initial post is that it would have made sense to me to do away with the 12v battery altogether, and let the hybrid lithium battery do everything (with proper battery and voltage management, of course).

 

[drmanny3]

My bad on the brand name Anti Gravity. I should have read the first post more carefully. Still wondering about the charging system for our cars. It appears that all three electric motors act as generators, but I could not find any information concerning how the 12 volt battery is charged. 12.2 volts seems a bit low from my experience especially if you are running a lot of accessories. Again what was your source of information?

 

[nsx878]

I have always been under the impression that the NSX did not have an alternator, and there fore the battery(S) were somehow charged via the electric motors under braking being turned into a dynamo..... I was also always under the impression that the car had no conventional starter and uses the ring electric motor as the starter...... Very clever in my opinion, but I'd imagine this sort of technology has been employed in hybrids for a long time?????

 

[PrimeMvr]

From the owner's manual

Battery Types
There are two types of batteries used in this vehicle; a standard 12-volt battery that powers the airbags, the interior and exterior lights, and other standard 12-volt systems; and a High Voltage battery that is used to power the propulsion motors and recharge the 12-volt battery.

There is a chart on pages 10-11 that show how the HV battery is charged by the direct drive motor under certain states and the front motors under braking.

I can't find the reference for this, but the direct drive motor is the starter and is powered by the HV battery. If both batteries are dead, you can jump via standard 12 volt. It goes through a voltage converter, I assume to charge the HV until it has enough juice to spin the direct drive motor.

 

[drmanny3]

I went on line win Honda and did not find any specifications on how the 12 volt battery charges. Other than the voltage is checked as are other parameters associated with the battery. Nothing about how the charging is maintained. If you drive under 6 miles there apparently is little charging that takes place and if you are running a lot of accessories you might drive the battery down in charge. I suppose I could put a meter on the battery to see what is happening before starting the car and during idle to see what happens.

 

[drmanny3]

Social distancing has provided me with not a damn thing to do but waste my time screwing around in the garage. So I checked the battery voltage of my OEM Battery after it had sat for the last 3 days without being started. This is what I measured with a digital RMS Meter:11.985 volts having sat for three days14.585 volts after starting and running in Sport+14.592 volts while cooling fans running for short duration 14.585 volts just at idle12.425 volts shut off12.195 volts 5 minutes after shut down12.110 volts 10 minutes after shut downThe original poster mentioned that he observed that the voltage would drop, falling below 12.4 volts during operation due to Acura's Smart Battery Charging System. I tried researching but could not find any reference to the Smart Battery Charging System. I went on line at Honda's Tech Site and could not find a reference. So not sure where this person found that information. Does anyone here know whether or not it is accurate or true? I do recall that my Shorai LFX36L3-BS12 LFX Lithium Iron Light Weight High Performance Motorcycle Battery minder would periodically allow the charge of the battery under tender to drop a certain amount and then proceed to charge up to appropriate voltage. This was done to insure the battery was conditioned and remained viable. Even when it was allowed to drain, I could still immediately start my 2001 Supercharged NSX. I am debating as to whether it is worth the effort to pull the OEM battery and replace it with a lighter battery. While it would register in terms of weight savings, not sure the improvement would result in any benefit other than a cosmetic look. For my Shorai someone made a really good looking aluminum holder for the battery. The package looked super. At 3800 lbs. the car is heavy enough such that a 35 lb. savings would only represent approximately 1% reduction in weight. If it were rotating mass then that 1% can make a difference as many cyclist will tell you when they try a really light weight wheel on their bikes.

 

[Chawumba]

OP here, DrManny, your information confirms what I was told by the folks at AntiGravity, that certain cars with "active" battery management (ours appears to be one) are problematic for the Antigravity battery line that has the restart feature - because the antigravity battery turns itself off when voltage drops to 12.4 volts. So what happens when using one of their batteries in a newer NSX is that at some point during the drive, the battery voltage goes low enough to trip the smart battery, and then when you shut the car off, everything goes dead. You then have to pop the hood, access the "restart" button on the Antigravity battery to get the car started again. Obviously not acceptable.

The solution is to get one of their batteries without restart. I swapped in the Antigravity ATX-30-HD battery (without restart) and its working fine. But as you say, $400 to save 35lbs likely not a great investment. Plus you have to modify the factory battery insulation box (it is a cool setup - vents cool air in from under the car, circulates around the battery and has a small computer type fan that pulls the hot air out of the battery box). Anyways, did it with some cutting and taping and all seems ok, but this is not a modification for everyone. I do like that I've removed weight up front that was rather high up, and my mind tells me the car points just a tad sharper going into turns....

 

[Chawumba]

Wow, I've been a member in good standing in half a dozen forums with previous cars I've owned, never had so many (well, actually any that I can remember) posts held up for review by moderators, never to be seen again. What am I doing wrong? Can't even seem to reply to my own thread to help share info with a forum member.

 

[sled driver]

Ditto that Chawumba.

Jimmy aka sled driver

 

[DocL]

Wow, I've been a member in good standing in half a dozen forums with previous cars I've owned, never had so many (well, actually any that I can remember) posts held up for review by moderators, never to be seen again. What am I doing wrong? Can't even seem to reply to my own thread to help share info with a forum member.

As long as your name isn't Tamoske you should be okay to post.

If you're referring to the 2nd Owners Forum, you need to provide a VIN as proof you own the car.

 

[Chawumba]

Don't know what or who Tomoske is, but I'm definitely not one.

 

[Bho]

Which Anti-Gravity model battery did you get for your NSX? Any issues with it running in your NSX? I have had an Anti-gravity in my motorcycle for years and an Earth-X battery for my Lexus RC F, debating which one to get.

 

[Chawumba]

Your information confirms what I was told by the folks at AntiGravity, that certain cars with "active" battery management (ours appears to be one) are problematic for the Antigravity battery line that has the restart feature - because the antigravity battery turns itself off when voltage drops to 12.4 volts. So what happens when using one of their batteries in a newer NSX is that at some point during the drive, the battery voltage goes low enough to trip the smart battery, and then when you shut the car off, everything goes dead. You then have to pop the hood, access the "restart" button on the Antigravity battery to get the car started again. Obviously not acceptable.

The solution is to get one of their batteries without restart. I swapped in the Antigravity ATX-30-HD battery (without restart) and its working fine. But as you say, $400 to save 35lbs likely not a great investment. Plus you have to modify the factory battery insulation box (it is a cool setup - vents cool air in from under the car, circulates around the battery and has a small computer type fan that pulls the hot air out of the battery box). Anyways, did it with some cutting and taping and all seems ok, but this is not a modification for everyone. I do like that I've removed weight up front that was rather high up, and my mind tells me the car points just a tad sharper going into turns....

 

[Chawumba]

Did a long write up on this with pros and cons, but it seems lost in moderator land and won't post. in short, with a fair amount of work customizing the battery cooling box, I was able to fit a ATX-30-HD - and be sure to get the one WITHOUT restart.