I've had the Ionic hooked up for awhile now and seems to be working well. It charges to 13.7 while driving my 2024 350h, and standby mode light goes green. Car off, It gradually drops to 13.3 v with each cell at 3.33, standby light turns yellow. The Ionic held that charge for a week test period so I think the yellow standby is normal function. Next, I ran my 12v battery down pretty low to 11.70v with 2% battery charge (car's electronics still functioning e.g. opened doors, etc. so maybe the replacement battery helped). I turned the Ionic on with13.3v, 90% showing and it started charging the 12v. In 5 mins, it charged the 12v to 12.75v and 11%. Turned off the Ionic which only dropped to 13.1v and 84% charge. So I'm reasonably assured the Ionic is a good backup plan. I'm also tracking digital app drain. The app auto-communicates on approximately 2 hour intervals and uses around 0.10v overnight.

 

Nothing has changed with our 20K miles one year-old RX450h+. About 20 minutes of charging and then no more during a 4 hour drive, until I put it in park.

 

Six hour trip in snow storm with a couple stops. Brief high charge then to 12.88. Note 11.88 drop during a 15 min stop and car would not start, dash message said hold fob to start button? Brand new fob battery installed and battery drop to 11.88? Front sensors were iced over, car turned off, wife was inside and locked doors while I went for BR break, then unlocked to re-enter. Maybe the security system disabled start from passenger lock/unlock? Battery at 12.56 when trip ended.

 

Thanks for adding hard data - that adds value to the thread.

I have noticed that the Lexus-factory battery drops significantly in its output voltage on load/current-draw. That drop probably exceeds what is to be expected from a run-of-the-mill 12 V battery - as the factory-battery is not run-of-the mill. So I would suspect that the 11.88 V drop likely happened due to heavy current load in the car for some reason, in case you are trying to understand. Not sure what exactly would've caused that temporary high current draw - but all the sensors being iced over could've something to do with that (?)

I managed to force the SA at my dealer to test my 12 V battery with their battery tester, when I went in for their 10K mile service - despite all his gaslighting. I was looking for a printed report, as is, from the 12 V battery. The SA went and externally charged the 12 V battery, and then tested the 12 V battery, and sent me a photo of the tester screen - which showed "Good Battery" along with an irrelevant CCA that is far higher than its rating. The voltage was above 13 V - which of course is natural if they just externally charged the battery and then tested it. In any case, at least managed to get a data-point of the battery health (haven't bought a battery tester, and will not do so). When I drive the car, the voltage stays at 12.3 - 12.4 V - with the occasional rise to 13.6 or 14.1 V.

 

Thanks for the input. I'm leaning towards a security/imobilizer feature. Read some others had similar issues and suggested the car wants to authenticate the owner is trying to start the car by using the owner's fob to start the car. Might make sense since my wife was in the car, without the fob, locked the doors, and then unlocked the doors for me to enter. Still doesn't explain the brief voltage drop to 11.88 on a decently charged battery.

 

As some of you may recall, I purchased two Ionic Emergency Start modules for my two 450h+ vehicles. One of them works as expected and the other one has begun acting up. To be more clear, after charging the 12v battery it reads 100% and over 13.8v. The next morning the voltage had dropped to 27%, which leads me to believe that there may be some bad lithium cells inside the pack. I'm guessing that this thing is comprised of a block of 18650 cells wired in series and some of them have gone south. Has anyone else noticed a voltage decline in theirs ? I'm going to contact them next week and see what they have to say.

 

What do you mean by "voltage had dropped to 27 %" ? The app doesn't show any %-values, hence asking. It could be a Quality Control issue - you can likely get it exchanged - I read reviews/forums of people having done so.

I have not seen any degradation, and in the Ionic App, for me, the 4 "cells" shown have voltages about 3.45-ish Volts everytime the car charges it up. The lowest floating voltage I've seen on it is about 13.2 V - and in discharge conditions, the lowest I've seen it drop is 12.9 Volts.

Do you have a ES1200 or ES1600 ? FWIW, mine's firmware updated to version to PSA1.0.15 as soon as I had connected with the App the first time.

 

LIke yours, I have the ES1200 and my firmware is the same, PSA1.0.15. The voltage %-age is shown in both the basic info screen (next to the little green battery) and the the next screen, U.I.T.C., where it is shown as a bar graph. Both indicate 27% and 12.7v. Individually, the four separate cell banks are all above 3v, at 3.14v to 3.17v. The 18650 Liion cells are normally 3.7v each so, it's odd that they would be discharging across the board so rapidly in less than 24 hours.

 

Yes, even though I haven't discharged mine for over a month now - the voltages are 99 %. Also, each time the car starts/charges its Lexus 12 V from its inverter, it also charges up the ES1200. So there seems to be something off with this unit of yours - given the 4 separate cell banks are having far lower values than expected as well - so the unit could just be defective. Lithium Hub are very prompt with warranty replacements, I read in reviews. And its good that we are able to see all this parametric data, so that we can know there's a problem.

 

My other unit seems to sit right at 99% nearly all of the time so, I am in agreement. There must be a defect in this one.

 

I confirmed that the anti-theft/immobilizer system is one reason the start button does not function normally sometimes, and the dash display shows the hold brake and touch fob to start button message.
This happens when:
- The fob/owner leaves car, someone inside locks and unlocks doors, fob/owner re-enters car, dash message says hold brake & touch fob to start button (security/anti-theft feature)
- (or) Owner uses digital key (phone app) to lock then unlock car, fob/owner enters car, hold brake & touch fob to start button (security/anti-theft feature).
NOTE: You may have to press the start button a second time with the fob to get the READY message.

 

Ironically, I bought the same NOCO after my brand new Chevrolet Colorado Z71 battery died. Guess why it died? Bad battery from factory.

It’s the battery suppliers or green crap most likely.

 

Folks, just wanted to share some OPEX (experience) on the 12V battery issues on my RX350h. Car purchased in July 2023. The mileage is relatively low (13K kilometers) because I don't drive to the office regularly. The battery died first time in March 2024 after I came back from a 3-week vacation. Note that the car is parked in the underground parking under pretty much ideal conditions, i.e. no extreme heat/cold and not precipitation. After March, the dead battery situation repeated at least 5 more times, and recently was very frequent, like once every 2 weeks or so. In the garage, I can't use a battery tender or anything like that. Lexus Roadside or CAA helped boosting the battery every time without any issues. But I got really fed up, wrote a stern email to the dealership's supervisor and asked to replace the battery. And so they did a couple of days ago. At the same time I purchased NOCO GB150 from Amazon because they had the best price (~$430 CAD, including taxes). GB150 has barely enough cable length to install the device as pictured in the manual. I fully charged GB150, and put in a zipped bag on the floor behind driver's seat, so that I can grab it quickly when needed. Cheaper NOCO products are NFG because of the cable length shorter than my .... Two more things: 1) I disabled the remote key access option as was advised by one of the people here; not sure yet if this helps long term; 2) the fuse cover, where the positive terminal is located, is made of such a hard plastic that I almost had to apply excessive force to unlatch it for the battery boosts. Guess what I did: on the clean edges and the "dog leg" of latch I applied a very thin layer of all purpose neutral silicone grease so that the latch opens easily next time I need to access the terminal.

 

The GB150 is overkill unless you are jumping a semi truck.

Perhaps you can return to save a few hundred dollars and jump the battery directly.

 

I know that GB150 can turn on a Piterbilt engine, and is an overkill for Lexus. But I want to follow the Lexus manual, and thus need sufficient length cables which is available only in GB150. Tinkering with e.g. GB40 and modifying/splicing the original cables is NOT a good idea because these are extra flex copper cables and are very tricky to handle. You better invest into GB150.