UTRacerX9

Back for an update. So I eventually received a new battery cable, but it wasn't overnighted, I got it yesterday afternoon. I don't know if the problem was with the seller or with UPS but whatever. The new cable was as it should be, and I began the conversion this morning.

First off, a huge thank you to Schnave for his well documented efforts here. If you follow his instructions, you will have zero issues.

This took about 2 hours from start to finish, including prep and cleanup. Very straight forward. The hardest part for me was the removal of the old negative battery cable. I do have ratcheting box wrenches, but they only helped a minor amount. I'm not a huge guy by any means, but my fingers and hands are big and after I got the nut off to remove the cable, I could not for the life of me get the nut started to tighten down the new cable. I probably spent 20+ minutes trying and swearing before I gave up and enlisted my 10 yr old daughter, she was able to get her hands under the carpet just fine and get the nut started and then I finished with the wrench. My carpet didn't have much stretch or give to it, so you may want a helper with small hands for that step.

Other than that, everything went fine. I did not elect to reuse the battery tie down strap, as mine got twisted and mangled a bit when I pulled out the old battery, and there is a metal ridge at the bottom of the battery compartment that, when combined with the battery tie down plate, hold the battery securely in place when you have it sitting properly. Once the battery was installed, I turned on the car and got the expected warning messages (I was already getting them all the time on startup.) Turned it back off, turned the key to start/accessory position, and inserted the dongle as instructed. Mine beeped 5-6 times almost immediately, I removed it and then started the car... no more battery lights or warnings.

Drove for about 20 min just to see if everything was fine, no issues popped up, so this appears to be a complete success for switching to an AGM battery. Battery voltage now reads a steady 14.3-14.4, and considering what the dealer wants to charge for a lithium battery even after supposedly cutting the price down to $1k, this is still cheaper and more reliable long term in my opinion.

Schnave, thanks again for being the trailblazer here, if you're ever in the Dallas area, hit me up, I owe you a drink or two!

Schnave

Are you saying I have small hands, and therefore a small . . .? I’ll have you know that I had to remove my very large watch to fit my hand under the carpet! 🤪

Kidding aside, congrats on an otherwise trouble-free installation. As far as I know, you’re only the second Rennlister to install the kit. This should give others the confidence to upgrade to the AGM battery at the first sign of trouble from the aging LFP batteries.

PorscheACC

Congratulations.. And indeed, Schnave was a key pioneer in this kit installation, and kudos for the guy (Kingstone?) who took took the personal time to talk to other companies to create and make this Lithium-to-AGM kit possible, after Porsche decided to cash in on defective batteries ($2,000) and outrageous simple battery installation/registration labor ($1,000)

I bought the kit and now decided to wait until I got a battery error message before installing the kit and buying the AGM battery..

I checked my battery charge with scanmer, and it still shows a healthy state.

I bought the kit, and took it to all my latest trips, because I didn't want to get stranded on a remote highway and have no battery for weeks or months and have my vehicle store in some far location across the US.

runbuh

IT'S ALIVE!!!!

@Schnave and @kingstone - The battery in the wife's 2019 Cayenne S, with no special high power draw options, is slap **** dead. My usual tricks of waking up the battery with my 75A charger, and then trickle charging, aren't working. It's just gone, man. No warning. Therefore, armed with the information and tools you've provided here, I'm going in. Got my battery from Costco. $169.99 + $15.00 core. Picked up a couple of extra plugs/wires since I'm likely to break something.
https://costco.interstatebatteries.c...option=2336344

One hour later - old battery is out, new negative cable is installed, and vent adapter is connected. The ratcheting box wrench and my, uh, statistically normal-sized hands, came in handy. I had a lot of trouble getting the battery's metal hold-down bracket to come loose. I think the battery base (where it flares out to go under the bracket) had pressed the metal bracket up against the threads of the rear-most bolt. I rocked the battery side to side and the bracket simple popped loose. Time to go do the LIN wiring. Note that I also had to talk to my neighbor for a bit. This probably only took 40 minutes.

See further below - the "plug" (boot) was somewhat buried in my LIN connector. I had to use a paper clip (from the other end) and some needle-nosed pliers to carefully work it out.

I got very waylayed when I figured out that my L-shaped bracket wasn't going to work (pictures coming in a few minutes). I used a Dremel to score a deep line, then bent off the "thumb" of the L, then used the Dremel to smooth out the edges (actually smoothed out a lot of it, it had a lot of sharp edges). This set me back a good while as using the Dremel, the only good tool I had for the job, was very slow work. Also, my positive cable assembly was just like what was shown in the YT video (two "150" connections, and a missing nut).

The last picture was a real "Doh" moment as I had not folded the battery carrying handles into place before putting the bracket on. That cost me a few more minutes to fix (had to take off the positive assembly, undo the bracket, fix the handle, and put it all back together). Sharp-eyed readers will note the red cap clearly visible in the very last picture, but in the wrong place. The positive terminal on the battery goes towards the rear. I was a bit paranoid about the negative cable touching the battery post when I didn't want it to (yet), so I moved the red protective cap to the negative terminal once the positive cable assembly was attached to the battery. I removed the cap, of course, just before I attached the negative cable to the battery.

I connected up the negative terminal, there was a nice click, and the interior lights popped on. I tightened everything up, put the cover in place, and started the car without issue. EXCELLENT. I got the errors as mentioned in the docs. Cut the engine off, but left the car on. Plugged in the Launch, did the "change battery" feature, set the amps to 95, type to AGM, set the manufacturer to "Int" (3 characters is all you get), and set the serial number to a 10 digit bogus number. The check engine light went away, then the whole car went dark. I cut the ignition fully off, restarted the car, did a couple of laps around the neighborhood, and then drove around town for 30 minutes. When I got home, I hooked up my non-lithium trickle charger and started charging. It was on three out of four bars at first, then all four/solid green/done about 20 minutes later.

Schnave

Great write up @runbuh. Keep the details coming. Each installation so far has had a unique small glitch that others can learn from. @UTRacerX9 needed more space under the carpet and you had a sticky hold-down strap.

My blue LIN dummy plug came right out when pushed with a wire or paper clip. You’re almost done — just use care when inserting the 12V pin into the LIN connector.

Looking forward to more details of the rest of your installation and ultimate success.

As these LFP batteries continue aging, they’re going to start dropping like flies. Glad we have an affordable alternative to LFP batteries.

Mech33

Sounds like you are going to code for AGM battery with a tool other than the blue dongle referenced in this thread. Is this easy to do with Launch or PIWIS?

Also are you using a harness kit referenced in this thread, or an OEM AGM harness part number?

runbuh

I used the kit that I bought from ABL (https://www.allbuylow-autoparts.com), but I worked with @kingstone to buy it without the blue dongle as I already have a Launch. It look less than 5 minutes to code the new battery with the Launch, but I have done that work before. I will say, if you don't have a Launch, the blue dongle makes this a very simple process.

mendes9

So does the dongle software do the same as you did on the launch and nothing more? Shoot i have an autel that i think can register the battery also, that could save a few bucks and you know exactly what was changed.

runbuh

I do not know, for sure, what the dongle does. At a minimum, I would think it needs to set the battery type to AGM, and clear the error codes (to clear the check engine light, for example).

PorscheACC

Which AUTEL model do you have?

I know the Autel MK906BT with coding only can register the battery, not change the coding from Lithium to AGM.

And, bedides that, I don’t recommend AUTEL, since they eharge you half the price of the device every year to subscribe and keep your coding and any other online features on.

AUTEL deceptively does not tell you that your device coding, etc, will become useless if you don't pay the exaggerated subscription, which was around $600 per year when I first bought mine.

runbuh

I have a Launch, and it's much cheaper to renew if you just want the Porsche updates. @mendes9 has the Autel. I have very little experience with Autel units, but the few (non-Autel) battery registrations programs I've seen included a battery type option.

PorscheACC

Let me try to understand the registration capabilities..

Are you saying that if a device battery registration option has Lithium, AGM, etc.. it will not only register the battery but will also recode the new battery type into the Porsche BMS?

When I re-registered my Lithium battery using my mk906bt device, because of some charging issues, the list of dummy registration battery options was just for you to register the Lithium battery options because that is what was installed in the BMS..

I don't see the AGM option on the Autel mk906bt, but don't know what the other options mean..

Or maybe, the Autel mk906bt is too elemental for performing battery type updates?

runbuh

That's all I did. My Launch had an option for "Binary-AGM", which is what I used. However, after doing some research today, I believe that "Fleece" is the setting we should be using, but I want to do some more checking (specifically with PIWIS).
https://www.battery-kutter.de/main/e...AGM-batteries-

AGM batteries

The lead-fleece battery – also called AGM battery (Absorbent Glass Mat) – is a sealed, valve-regulated battery. Thanks to the built-in glass fibre fleece, the AGM battery is secured against leakage of the electrolyte (acid), when used in all positions

PorscheACC

Thanks, great usefull information.. didn’t know that..

runbuh

PIWIS shows different options, and seems to have only one AGM option. I may go use PIWIS on my car tonight and code it "properly".