Leaking battery during Autocross & Trackday

[RZNT4R]

Originally Posted by FR-S2GT86

Technically, I didn't misunderstand.

No no, no need to be humble, this is the exact definition of a misunderstanding, though likely stemming from translation shenanigans. The image just above your screenshot also fails to convey the full meaning, but coupled with the note in blue, it hints at a translation error or a lack of context. One is described as 3-pin control while the other as JST single-pole LIN control but the note below says "changing from 3 phase wire to single-pole". The note should have said "changing from 3-pin to single-pole" if it was referencing the control method or clarified if it was talking about the stator windings which have gone from delta to star type.

Also attached are the internal schematics for the 2016 and 2017 alternators, You can see they both use multi-phase stators, but the 2017 is even doubled up! 6 stator circuits, two diode bridges, this is a 140 AMP monster.

[FR-S2GT86]

Originally Posted by RZNT4R

No no, no need to be humble, this is the exact definition of a misunderstanding, though likely stemming from translation shenanigans. The image just above your screenshot also fails to convey the full meaning, but coupled with the note in blue, it hints at a translation error or a lack of context. One is described as 3-pin control while the other as JST single-pole LIN control but the note below says "changing from 3 phase wire to single-pole". The note should have said "changing from 3-pin to single-pole" if it was referencing the control method or clarified if it was talking about the stator windings which have gone from delta to star type.

Also attached are the internal schematics for the 2016 and 2017 alternators, You can see they both use multi-phase stators, but the 2017 is even doubled up! 6 stator circuits, two diode bridges, this is a 140 AMP monster.

I appreciate the further explanation on the topic and I’m sure the OP and the rest of us here do as well. Humbleness, though, is not one of my attributes. I’ll admit that the note in the blue square of the attachment to OP’s post #24 is MISLEADING, however, I am not misunderstanding the fact that there has been a significant design change to the charging circuit between 2016 and 2017.

And you’re still correct that (as long as nothing else has been modified) the installation of a newer style alternator will not work in the pre-revised version of the car. I will note though, that the body of the alternator does not appear to have significantly changed, so it looks like it would be possible to physically bolt the new alternator into place, but would be impossible to DIRECTLY wire up without also modifying the existing wiring harness and plug. Of course, if someone were to do that, they would most likely immediately get a CEL with DTC’s indicating a charging problem and possibly cause damage to the ECU in the process. Which does not appear to be the case here, as OP has not mentioned any CEL to accompany his multiple battery leakage issue.

What I’m trying to do is look at the problem from a different perspective and asking questions of possible situations that may also cause the multiple battery leakages. The top reason, I believe, under NORMAL driving situations for a new battery to leak would be overcharging, however that may happen.

When we throw in the fact that OP is tracking his car when this problem occurs, we know that extra heat is involved in the equation. In certain circumstances, such as a breakdown of internal electronics within the charging system due to high heat, that becomes an additional factor when attempting to diagnose the main problem.

What we really need to see to rule out a charging system fault is a data log from OP during tracking of the car to look at the voltage the entire time, and then pop the hood (bonnet) to see if the battery is leaking afterwards. If the battery leaks with no indication in the log of an overcharge, then that would rule out an overcharging condition as the direct cause of leakage.

The next best explanation, in my opinion, is sloshing of the battery fluid inside the cells due to tight turns, which can be remedied by A) no more tracking of the car or B) a different style battery. But remember, the charging circuits in these cars were not designed for AGM batteries, as those batteries have different charging requirements altogether from lead/acid batteries.

[Delmar]

Hi guys, just an update. I got a new battery and had the car load tested (checked with 2 different kinds of tester). Also revved it up to 4,000 while it was being checked and the guy said it was all good.

So could it be that it was really the battery?
Or the current sensor?

Also I'm not sure if this matters but my aftermarket headers aren't heat wrapped, so could this cause the engine bay to experience intense heat to the point that it affects the battery? Or am I just over analysing the issue.

[RZNT4R]

Heat is worse for a battery than cold, so even if that isn't the issue, looking into a battery blanket wouldn't hurt.

Is the new battery gel or agm? Vent tube?

[FR-S2GT86]

Originally Posted by Delmar

........Also I'm not sure if this matters but my aftermarket headers aren't heat wrapped, so could this cause the engine bay to experience intense heat to the point that it affects the battery? Or am I just over analysing the issue.

No, you're not overanalyzing the issue, but it would probably have been beneficial for you to inform us of this small tidbit of information at the beginning. I've now changed my mind on the diagnosis.

The fact that you're tracking your car with UNINSULATED aftermarket headers is now my number one choice of what's causing your batteries to leak.

Combine high heat build up just from tracking your car, with the added EXTRA heat from thinner-walled and uninsulated headers, and your underhood temperatures surrounding the battery are probably so high that the pressure inside the battery is high enough to push the electrolyte liquid out through the vent holes where normally you would only get Hydrogen gas out the vent holes.

Here's a test you should try:

Set up a remote thermometer right next to or above the battery and drive normal as you would on the street, monitoring the temperature, then on your next track day compare that temperature to what you see on track day. Take that information and check the battery manufacturers' recommended maximum ambient operating temperature and you will probably find the reason why your batteries keep leaking.

[Delmar]

Originally Posted by RZNT4R

Heat is worse for a battery than cold, so even if that isn't the issue, looking into a battery blanket wouldn't hurt.

Is the new battery gel or agm? Vent tube?

Neither of those, since I'm waiting for the Optima to restock their yellow tops. But I asked around with a few people who track their car a lot and they're all using this brand of maintenance free battery so I decided to use this for the mean time.

But also since @FR-S2GT86 said the charging system isn't designed for AGM, I might look into other options 😅

[RZNT4R]

Originally Posted by Delmar

Neither of those, since I'm waiting for the Optima to restock their yellow tops. But I asked around with a few people who track their car a lot and they're all using this brand of maintenance free battery so I decided to use this for the mean time.

But also since @FR-S2GT86 said the charging system isn't designed for AGM, I might look into other options ��

It isn't, but the charging system isn't that smart in the pre-17 cars. The difference is AGM will take less charging amps, and so charge slower. That would be bad in a 2017 as the car lowers charging voltage in normal operation, using the battery sensor to keep the battery always below full. A lower charging voltage means less load on the alternator so slightly better fuel economy. This charging headroom is used under deceleration and the car uses the free inertia to load up the alternator and crank the charging voltage to the max momentarily. This isn't the ideal use case for an AGM, what a 2017 needs is a battery that can take a high charging voltage and has fast current absorbtion, so flooded is best.

But for a -2016, you probably won't see a significant difference in charging system performance with agm.

[Delmar]

Hi guys, just an update. Finally confirmed the source of the issue. I just came from the track a few days ago. I changed my battery to a different brand as previously stated and wrapped my headers like you guys reccomended.
And I'm glad to say that my new battery didn't leak!


I'm pretty certain the main source of the issue was the battery.
I was with a friend too that day, (almost stock Toyota Vios with stock headers) that was using the bad brand of battery that I used to have. His leaked a few months back TOO after some autocross but he had his battery replaced under warranty. Since I started to suspect that it was an issue with the battery and not the car, I brought some baking soda to the track to neutralize the battery acid if it did leak again. I was expecting that HIS battery would leak, and sure enough it did toward the end of the day... I however changed to a different brand and the whole day I didn't have any issues with my battery leaking anymore

TL;DR: issue was solved when I changed battery brand and wrapped my headers. Friend didn't change brand and his battery leaked on the track.

[x808drifter]

Originally Posted by Delmar

Hi guys, just an update. Finally confirmed the source of the issue. I just came from the track a few days ago. I changed my battery to a different brand as previously stated and wrapped my headers like you guys reccomended.
And I'm glad to say that my new battery didn't leak!


I'm pretty certain the main source of the issue was the battery.
I was with a friend too that day, (almost stock Toyota Vios with stock headers) that was using the bad brand of battery that I used to have. His leaked a few months back TOO after some autocross but he had his battery replaced under warranty. Since I started to suspect that it was an issue with the battery and not the car, I brought some baking soda to the track to neutralize the battery acid if it did leak again. I was expecting that HIS battery would leak, and sure enough it did toward the end of the day... I however changed to a different brand and the whole day I didn't have any issues with my battery leaking anymore

TL;DR: issue was solved when I changed battery brand and wrapped my headers. Friend didn't change brand and his battery leaked on the track.

So did the type of battery stay the same?
Meaning you got a different brand maintenance free battery, not an AGM.
Old brand vs new brand would also be helpful so others don't make the same mistake.

[Delmar]

Originally Posted by x808drifter

So did the type of battery stay the same?
Meaning you got a different brand maintenance free battery, not an AGM.
Old brand vs new brand would also be helpful so others don't make the same mistake.

Yup, I used the same type of battery (maintenance free). Just a different brand.

Old brand was Motolite and new brand is Amaron... I haven't seen Motolite in other countries though, I may be wrong. It's supposed to be one of the best selling batteries here in my country (Philippines) I've asked a few people and I heard their product quality has been declining recently.

Edit: The exhaust wrap I put is Thermo-Tec if anyone is curious.

[blsfrs]

On track, I had the same problem with a "Everstart" battery that came in my FRS. A Optima red top solved the problem.

[gatorac]

My latest BRZ is also puking battery acid down the trans tunnel on it's track day. EverStart battery. It's made a mess. A guess an AGM battery is my next upgrade.

[Decep]

I don't even track and i get this too on my Interstate (costco) battery. I just put some baking soda and water and wash it every once in a while.

[Grady]

Originally Posted by RZNT4R

It isn't, but the charging system isn't that smart in the pre-17 cars. The difference is AGM will take less charging amps, and so charge slower. That would be bad in a 2017 as the car lowers charging voltage in normal operation, using the battery sensor to keep the battery always below full. A lower charging voltage means less load on the alternator so slightly better fuel economy. This charging headroom is used under deceleration and the car uses the free inertia to load up the alternator and crank the charging voltage to the max momentarily. This isn't the ideal use case for an AGM, what a 2017 needs is a battery that can take a high charging voltage and has fast current absorbtion, so flooded is best.

But for a -2016, you probably won't see a significant difference in charging system performance with agm.

I have had zero issues with a red top in my 17.