I don't know what to say about the test. I've been using it for many months and I've left my car unstated for over 2 weeks and it still cranks my car with a supercharger on it. My expectations were realistic and it's way exceeded them. It's definitely a lightweight race part, not for everyone.
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Lightweight battery, odyssey, braille, etc. Information:
- Thread starter TURBO2GO
- Start date
I've been tuning quite a lot lately. I've been monitoring my engine's vitals probably closer than ever before.
Something we noticed. At about 5k rpm and above the alternator shuts down. I can't confirm this yet but in reviewing my logs the car's voltage will dip slightly and maintain a 12.0V readout until redline. For track guys... this would be a consideration since you can easily spend 20mins + on the track at above 5k rpm with a lot of current draw from only the battery.
Something we noticed. At about 5k rpm and above the alternator shuts down. I can't confirm this yet but in reviewing my logs the car's voltage will dip slightly and maintain a 12.0V readout until redline. For track guys... this would be a consideration since you can easily spend 20mins + on the track at above 5k rpm with a lot of current draw from only the battery.
It's not really a worry. It just means the battery has to be able to sustain the consistent draw of the fuel pump and other electricals like the cooling fan during constant high rpm operations. My Oddysey 680 doesn't have a problem. I have reason to believe the Shorai should perform better. Maybe the voltage will maintain something like 12.5V on my car hopefully.
I have no issue with fuel pressure dropping so i'm not worried.
Again, I can only observe this while studying the logs after the fact. There's no way I could notice this from the gauges themselves in real time lol
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#becauseracecar
I can hardly contain myself man... LOL
It's like a whole new world has been opened up to me. It's been fun as hell. It also helps that my car is running amazing right now (well, until it breaks again lol)
That's curious. Is your alternator standard setup? There's no mention of high-rpm alternator shutdown in the NSX Workshop Manual. There's a graph on page 23-102 showing the alternator is capable of producing over 90 Amps from 4000 rpm to redline.
Maybe it's not a shutdown, but extra electrical load ... due to VTEC perhaps ?
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I'm using the 1992 Prelude 90amp alternator that ships with every CTSC kit.
I agree. It seems to behave like an alternator shutdown but there's no way for me to verify this easily. I don't have any electrical components that automatically turn ON at 5k rpm consistenly like this. What VTEC components would you reckon might cause this?
I'll post a pictures of my data log graphs and we can analyze it together on a different thread. The alternator shut down seems most likely the culprit but if my fuel pressure still stays solid then I frankly don't really care to much. It would be good to know though.
my VTEC comments was only a [wild-ass] guess, it may be well off the mark. I'll look at the manual later to see if VTEC does draw much current ...
done 10 track days on the Shorei and no problem with the charge or starting again after cool down and with the two main tracks i use its always in vtec range most sessions are 15min. battery is still strong with over a year being in the car
Same here I have not had any issues and I have been on the track with it.
That's really interesting data. In real world usage, I've easily been able to start the car weekly with no problems. Is it possible for you to do the same test on a regular lead acid battery? I'm interested in how one of those would do using that test.
More charts
Sure, here's a couple:
1) my old Odyssey PC680, still usable but very tired and needs frequent charging - gave up 5.3 Ah @ around 6A
2) a Supercharge car battery, in reasonable condition - gave up 23.1 Ah @ around 6A
I use 11.5V as the lower threshhold for lead-acid batteries, but 12.2 V for the Shorai. When the load was removed from Shorai the O/C volts climbed back to 12.8 - 12.9 within a few minutes, I didn't want to discharge it any further, because there's no way I can be sure to stop just before it may damage the battery ...
The local Shorai dealer reckons the LFX36L3-BS12 battery is around 13 A/Hr and around 80% of that can be used. At lower current load the Ah are probably higher so I'll do further tests at lower currents (give me a few days). The most useful test would be the current drain of my NSX sitting in the garage, which will be well below 1 amp, and probably below 100mA.
Has anyone measured their garaged current drain? Although not all NSX will be the same, it would be helpful to know this for a few NSX's
Sure, here's a couple:
1) my old Odyssey PC680, still usable but very tired and needs frequent charging - gave up 5.3 Ah @ around 6A
2) a Supercharge car battery, in reasonable condition - gave up 23.1 Ah @ around 6A
I use 11.5V as the lower threshhold for lead-acid batteries, but 12.2 V for the Shorai. When the load was removed from Shorai the O/C volts climbed back to 12.8 - 12.9 within a few minutes, I didn't want to discharge it any further, because there's no way I can be sure to stop just before it may damage the battery ...
The local Shorai dealer reckons the LFX36L3-BS12 battery is around 13 A/Hr and around 80% of that can be used. At lower current load the Ah are probably higher so I'll do further tests at lower currents (give me a few days). The most useful test would be the current drain of my NSX sitting in the garage, which will be well below 1 amp, and probably below 100mA.
Has anyone measured their garaged current drain? Although not all NSX will be the same, it would be helpful to know this for a few NSX's
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I've done some measurements of my battery drain current at rest and posted the results in this new thread and asked for others to report theirs. In summary my average drain is around 110mA including some interesting spikes to 170mA every 5 minutes. I've also been recording voltage ups and downs in real life usage, and I'll report on that soon.
With around 10Ah usable capacity in the Shorai the current of 110mA means I need to charge the battery after around 90 hours or approximately 4 days at rest. That's about what I'm experiencing. But note my current drain may be higher than stock NSX, because i have a non-OEM security system. That's the question I'm chasing in in the other thread
With around 10Ah usable capacity in the Shorai the current of 110mA means I need to charge the battery after around 90 hours or approximately 4 days at rest. That's about what I'm experiencing. But note my current drain may be higher than stock NSX, because i have a non-OEM security system. That's the question I'm chasing in in the other thread
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My 2nd PC680 recently took a dump after 4 years of ownership. I seem to get about 4 years out of them. This time I wanted to investigate the lithium-iron offerings.
I like the Kinetic setup, but have heard of a lot of issues with the Shorai batteries. I wanted something with the A123 manufacturing techniques. Also, as an R/C hobbyist, I know the importance of over and under-charging the lithium batteries. Cell equalization is important for longevity.
I also wanted to keep my existing aluminum 680 mount.
So, after a long search, I ended up with the EarthX ETX36D. Should offer enough reserve for my 50ma alarm current drain and plenty of cranking power for my newer Denso starter. Fits in my shortened 680 mount. Has BMS circuitry built-in. Has a lot better reputation than Shorai. $350 shipped to my door. FULL 2yr warranty unlike most that are pro-rated. Engineered and assembled in the US. 10lbs lighter than my 680. We'll see how long it lasts....
Of course, the lightest system would be a bank of capacitors:
<iframe width="560" height="315" src="//www.youtube.com/embed/z3x_kYq3mHM" frameborder="0" allowfullscreen></iframe>
I like the Kinetic setup, but have heard of a lot of issues with the Shorai batteries. I wanted something with the A123 manufacturing techniques. Also, as an R/C hobbyist, I know the importance of over and under-charging the lithium batteries. Cell equalization is important for longevity.
I also wanted to keep my existing aluminum 680 mount.
So, after a long search, I ended up with the EarthX ETX36D. Should offer enough reserve for my 50ma alarm current drain and plenty of cranking power for my newer Denso starter. Fits in my shortened 680 mount. Has BMS circuitry built-in. Has a lot better reputation than Shorai. $350 shipped to my door. FULL 2yr warranty unlike most that are pro-rated. Engineered and assembled in the US. 10lbs lighter than my 680. We'll see how long it lasts....
Of course, the lightest system would be a bank of capacitors:
<iframe width="560" height="315" src="//www.youtube.com/embed/z3x_kYq3mHM" frameborder="0" allowfullscreen></iframe>
A very interesting + amusing / funny clip. Great ingenuity using a thick sock to "mount" the battery for a test run, and the roosters crowing every morning just before he gets in to check the voltage of his capacitor pack after car is off overnight, for 3 - 4 nights !
I wonder about the rush of current from alternator to cap-pack when starting after volts have dropped < 10v. Could be lots more than charging a low battery.
I wonder about the rush of current from alternator to cap-pack when starting after volts have dropped < 10v. Could be lots more than charging a low battery.
Thought I should update this thread for other considering Lithium batteries:
Within the past month I have bought and sold my EarthX 36-series battery. Why? Well, these cheaper ($500 and under) lithium batteries just aren't designed to work in car environments. Failure rate is high in this environment for a few reasons:
1) They are not designed for high charge current. The sudden rush of current to the battery after cranking can be 100+amps from our alternator. I should have checked before ordering my EarthX, but these small batteries are only designed for a MAXIMUM charge current of ~20Amps. Look on the sides of the batteries. I should have noticed before I bought the $350 EarthX, but I didn't until I pulled it out of the package! I gave their technical support a call to see if they would suggest use in my car and they wouldn't. EarthX said they are working on a new battery between their 36 and 48 that should work OK in cars, but they recommend the $700 48 series in the meantime. The only batteries to support high charge currents are the Lithium Pros and other $500+ batteries.
Will the small ones work with the high currents? Sure, but they degrade the cells performance and won't last long. Seems a lot of folks on here have already witnessed that.
2) They are not designed for high sustained discharge current. Most state don't crank an engine over for more than 5 seconds without letting the battery rest and cool down. Google LiFe thermal runaway for awesome pictures if you don't let your cells cool down. Again, the good $800+ batteries (Lithium Pros) have thermistors that measure the temp and use MOSFETs to disconnect the battery bus. Of course, this creates another failure point in your electronics, but it is better than your battery catching on fire.
Even if your cells don't melt, sustained high discharge currents will degrade cell performance and lifetime.
Read all of the warranties from the "cheapie" lithium battery manufacturers (shorai, antigravity, ballistic, etc). They'll only replace your battery once if it fails within the short, pro-rated warranty period. After that, you're on your own.
Otherwise, I would love to have one in my car. I just can't justify spending $900 though for a "good" one. Price is continually dropping , so someday I'll get one. In the meantime with my cold climate, I just bought an Odyssey PC950/ER30 to replace my old PC680. Only 20 pounds and proven reliability....
For all of you running the little lithium iron batteries... good luck!
My $0.02.
Dave
Within the past month I have bought and sold my EarthX 36-series battery. Why? Well, these cheaper ($500 and under) lithium batteries just aren't designed to work in car environments. Failure rate is high in this environment for a few reasons:
1) They are not designed for high charge current. The sudden rush of current to the battery after cranking can be 100+amps from our alternator. I should have checked before ordering my EarthX, but these small batteries are only designed for a MAXIMUM charge current of ~20Amps. Look on the sides of the batteries. I should have noticed before I bought the $350 EarthX, but I didn't until I pulled it out of the package! I gave their technical support a call to see if they would suggest use in my car and they wouldn't. EarthX said they are working on a new battery between their 36 and 48 that should work OK in cars, but they recommend the $700 48 series in the meantime. The only batteries to support high charge currents are the Lithium Pros and other $500+ batteries.
Will the small ones work with the high currents? Sure, but they degrade the cells performance and won't last long. Seems a lot of folks on here have already witnessed that.
2) They are not designed for high sustained discharge current. Most state don't crank an engine over for more than 5 seconds without letting the battery rest and cool down. Google LiFe thermal runaway for awesome pictures if you don't let your cells cool down. Again, the good $800+ batteries (Lithium Pros) have thermistors that measure the temp and use MOSFETs to disconnect the battery bus. Of course, this creates another failure point in your electronics, but it is better than your battery catching on fire.
Even if your cells don't melt, sustained high discharge currents will degrade cell performance and lifetime.
Read all of the warranties from the "cheapie" lithium battery manufacturers (shorai, antigravity, ballistic, etc). They'll only replace your battery once if it fails within the short, pro-rated warranty period. After that, you're on your own.
Otherwise, I would love to have one in my car. I just can't justify spending $900 though for a "good" one. Price is continually dropping , so someday I'll get one. In the meantime with my cold climate, I just bought an Odyssey PC950/ER30 to replace my old PC680. Only 20 pounds and proven reliability....
For all of you running the little lithium iron batteries... good luck!
My $0.02.
Dave
Good to see this information posted Mac. It's great to see others prepared to play on the bleeding edge. We'll only find good solutions through experimentation and honest feedback of the results, including failures. I killed my Shorai by simply leaving interior light on overnight ... dead as a doornail. Maybe I didn't have it long enough to kill it by exceeding the charge current limitations, or maybe that contributed to early death. As I reported earlier Shorai also have very small capacity, only around 10Ah
Now I'm playing with the 300+ Farad capacitors as described in your other thread, using a small 2W solar panel to compensate for leakage currents. I'm sure capacitors aren't the perfect solution either but they certainly can handle high charge currents, and they're light weight ... there is an answer we just have to find it!
Now I'm playing with the 300+ Farad capacitors as described in your other thread, using a small 2W solar panel to compensate for leakage currents. I'm sure capacitors aren't the perfect solution either but they certainly can handle high charge currents, and they're light weight ... there is an answer we just have to find it!
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I killed my Shorai as well. That was a shame too b/c it was such good looking and well engineered kit with the group buy.
Saw the PC950 at the local Batteries + store the other day and was going to ask if anyone has used it. My NSX is in "storage" for the time being so I think I'll wait on another battery until it's ready to run again.
Saw the PC950 at the local Batteries + store the other day and was going to ask if anyone has used it. My NSX is in "storage" for the time being so I think I'll wait on another battery until it's ready to run again.
Just piling on here, I had a Shorai that lost most of its capacity. It was the Li-Fe battery with the model number with 36 in it, probably the same as all you guys.
It wouldn't start the car after 2 days being parked when I got rid of it.
I would like another light battery so thanks for posting the other options out there.
It wouldn't start the car after 2 days being parked when I got rid of it.
I would like another light battery so thanks for posting the other options out there.
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That's awesome Sparky! Can't wait to hear about your results!
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I searched and couldn't find anyone here that has used the 950. 925, yes. But, when you compare battery specs on the Odyssey webpage, the 950 seems like the way to go (for a slight price increase of course).
If you search around, Odyssey battery prices vary quite a bit. For example, my local Batteries Plus has the 950 for $270. The Odyssey website store has them for ~$220 shipped. Online "Race Stores" sell them for $300, etc. Odyssey website store just had a SEMA promotion for 20% off their batteries too.
I made my own mount with a generic battery holddown kit from the local autoparts store along with some scrap aluminum angles. It is very robust and safe in a collision scenario.
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The technology is quickly changing and prices are coming down, but the lithium technology still has a ways to go for our applications. We'll probably have a robust lithium battery in the $300 price range in the next year or two.
Unfortunately, the Shorai's will die a quick death from over-discharge, or a slower death depending on every high-current discharge/charge cycle they endure.
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Mine has been running fine Since i started disconnecting it after each use. I killed the first one by over discharging
I'm not sure that's a good solution scammy. Every time the ECU looses battery power it will revert to default tuning on power up, then as you drive it adjusts tuning parameters based on actual feedback from your car (like O2 sensors). Regular disconnects means your ECU will always start in default mode then start relearning every time you drive.
seems to be fine i have had no issues with it at all I do have that RDX Tune so maybe it doesn't alter it at all since it is not a standard ECU anymore and I am about to go aftermarket there anyway.
but one thing I will say the battery was a pain in the arse to keep charged I had the Shorei charger and if you do not follow the correct plug in procedure it would not charge or if someone turned it off at the wall by mistake and then turned it on again that does not mean it is keeping it charged, that's how mine got to be buggered while it was sitting at my mechanics.
however since i just disconnect after each drive the battery holds that level and it takes me all of 2 minutes to hook it up each time so it does not annoy me to do this the battery should hold its charge for a very long time if disconnected and I have been doing that for over a year now with no issues so I am still happy with this setup over all others mentioned.
but one thing I will say the battery was a pain in the arse to keep charged I had the Shorei charger and if you do not follow the correct plug in procedure it would not charge or if someone turned it off at the wall by mistake and then turned it on again that does not mean it is keeping it charged, that's how mine got to be buggered while it was sitting at my mechanics.
however since i just disconnect after each drive the battery holds that level and it takes me all of 2 minutes to hook it up each time so it does not annoy me to do this the battery should hold its charge for a very long time if disconnected and I have been doing that for over a year now with no issues so I am still happy with this setup over all others mentioned.
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