If the battery is only 345 CCA, why wouldn't a 'bigger' battery (more CCA) benefit? Or at least, allow peace-of-mind?

More CCA would allow more drain capacity and still allow starting.

 

CCA is the instantaneous current capacity at 0 degF for a fully charged battery. The RX450h+ does not need that much current to "start."

The capacity of the battery is reflected in amp-hours or as Reserve Capacity. In our case, it is a 60 amp-hour battery. A larger capacity battery would allow more current drain and still be able to start, but we're talking about a fractional improvement, nothing dramatic. If someone has a battery dying in a week, the larger battery would give one an extra couple of days.

Keep in mind that replacing a deep-cycle battery with a larger capacity starter battery may actually make things worse, as the starter battery is not meant to ever be deeply discharged. A few deep discharges could destroy a starter battery, where a deep-cycle battery can shrug them off.

 

Charging requirements for a deep cycle battery are different from standard. As for the hybrid Lexus the charging system does not work the way we would think a charging system should work anyway as we are used to an alternator which actually would fully charge a battery on a long trip. The type of battery put in the car is important. I have seen nothing to suggest the battery is deep cycle but do your own research when time to replace.

 

Yes, alextv, agreed that the technology is same - just that Lexus has put in some effort such that this Panasonic battery isn't as bad as the usage/deaths resulting for a flooded lead-acid like bought off the Walmart shelf for $70. So my point was that (1) "some" co-design effort was put into the charging/battery for the hybrids, even if that was not enough, by Lexus, (2) GeneralKlinger's finding his car was alive at 11.76 V makes me believe the chart I linked to is more relevant for this Panasonic battery than the chart you found (per which chart, GeneralKlinger's car shouldn't have been alive at all).

These days dealers are giving out a replacement of a "Lexus-branded" battery, so I'm looking forward to getting Lexus to pay for it as soon as my Panasonic dies. I'm not going to babysit my $76 K car. And waiting for someone with lawyer friends filing a Class-action for this mess, so that I can join the Class

 

Most 60 amp-hour starter batteries have over 600 cca. That is what leads me to believe that the 450h+ has a deep cycle battery.

 

I purchased my '24 RX 500h F Sport 3 weeks ago and immediately had dead battery issues with it 2 days after purchase, but come to find out it was from the key fob. I have previously owned a Honda Pilot, Acura MDX and a Ford F-150 Raptor all with the new key fobs where I would leave them in the vehicles inside our garage. Never any issues.

I immediately detailed the Lexus one day after I purchased it to prepare it for ceramic coating where I spent literally 4-5 hours, washing, clay baring and fully polishing the vehicle. The entire time I kept the key fob in my pocket which according to Lexus, will run the battery down because the fob and vehicle continuously try to communicate with each other when they are located close by which runs the battery down. The Lexus technician said never store the key fob near or inside the vehicle or have it on you if you are going to be around the vehicle for long periods of time. Keep the fob inside your house. Also, don't store the fobs next to other Lexus fobs because they will try to communicate with each other which will drain the fob batteries down.

It happened twice all within 4 days of purchase and Lexus put a new battery in the rear cargo area. I've since purchased a booster charger on Amazon in the event it happens again. Hopefully this helps owners to prevent dead battery issues in the future.

 

Actually, I mispoke. It was actually at 11.75v. I am attaching the image here as proof The huge jump was when she started it before heading for groceries.

 

All of those little dips in the line indicate something is constantly communicating with the vehicle and draining the battery.

This is a day without ours being driven.

 

One thing to point out in your chart is there is not a downward spike at turn on which means there is minimal current draw to lower voltage. That voltage in a regular car most likely would not start the car because it would be below 10 v. Without looking at a schematic diagram of the module it is hard to tell what the minimal voltage requirement is for initialization. As the 12v is put on the module it is regulated down to operate the chips. The regulator determines the minimum voltage parameter to operate regulator. Toyota in there charging algorithm most likely takes this into account.

 

Wish I knew what it was LOL

 

Ok, good. So what we need to do if the battery is running low is by some groceries.

 

Does Lexus tell you in the owners manual or anywhere else what you have to do exactly to prevent excessive battery drain?

 

Maybe don't leave your lights on. Seriously most dealers have no clue there is a battery issue or have heard of a charging algorithm.

 

Would it make you folks happier if you knew it wasn't just Lexus hybrids?



I had to roll my eyes while watching the IndyCar race today (Sept 1 2024). The points-leader's new hybrid car died, right after the Start.
After multiple attempts at rebooting the engine, they fixed it by installing a new battery. Took them ~25 laps...

Misery loves company?

 

Say I have dead battery from sitting for several days. I am aware of the front engine contact points to jump start. However the car is parked in tight garage with another car. Assuming I can open the tail gate, is it safe to jump start from actual battery terminals?
I understand there is no way to release transmission to push back. This is nightmare scenario.