News
Why Tesla’s lead acid 12V battery needs to be lithium-ion based
It’s a prominent issue surrounding the electric vehicle market that the old-school lead acid battery just isn’t appropriate for new technology vehicles. Many users of electric vehicles, especially Tesla owners, have cited concerns with the poor performance of their 12V or low-voltage battery, oftentimes requiring annual replacement.
In contrast, a lead acid battery in a traditional internal combustion engine (ICE) vehicle generally has a 4 year life-cycle, but why?
RELATED: Tesla Model S 12V Lithium-Ion battery replacement (up to 70% lighter, 4x life)
First off, some of the most important factors to consider in longevity of a battery are “cycle-life”, environmental conditions, discharge/charge rates and calendar-life; cycle-life is how many times the battery can be drained and recharged in its life. Environmental conditions include temperature and humidity. Discharge/charge rates are the amperages going out of and into the battery respectively.
There are two major differences between the way an ICE vehicle uses its 12V battery and the way an EV uses its 12V battery:
“OFF” state discharge and cycling frequency
ICE Vehicle: generally has a very low 12V load while the vehicle is in the “off” state, often this load doesn’t exceed a few watts and doesn’t present a major challenge for the 12V battery to maintain.
Electric Vehicle: The 12V load while in the off-state is often much higher due to advanced computer systems that are running to maintain the high-voltage battery, keep vehicle “connected” (all EV have some remote access features), maintain charging and BMS (Battery Management System) communications, etc. In fact a Tesla Model S/X puts about 50 Watts of load on the 12V system when the vehicle is in the “off” state. 50 Watts equals about 4.5 Amps of discharge on the 12V battery, this drains the battery down relatively rapidly and requires the 12V battery be “recharged” by the high-voltage battery regularly, this usage pattern results in many cycles being placed on the battery.
“ON” state utilization and purpose
ICE Vehicle: The 12V battery is used to initiate the ICE (start the car) and is designed for putting out large amounts of current to accommodate this process. Once an ICE vehicle is in the “on” state, it relies on an alternator to power all of the 12V sub-systems and also maintain the voltage of the 12V battery.
Electric Vehicle: The 12V is subjected to (practically) no additional load while the vehicle is being turned “on”, and although most vehicles are designed with DC/DC converters (which act as alternators) it is often an engineering design choice to reduce load on the DC/DC converter by minimizing the frequency with which it is utilized. This also extends the driving range of the vehicle because none of the precious high-voltage battery capacity is being shunted to non-driving tasks. Due to this usage profile the 12V battery is subjected to relatively low discharge and recharge currents.
When you combine the high number of cycles and the low current requirements of the electric vehicle 12V battery system you arrive at a completely different battery need than that of an ICE vehicle. Lead Acid batteries are very good at high discharge and low cycle count life-styles, this is their bread and butter and this is where they last a long time and provide the most bang for the buck (cheap cost and decent product life-cycle), but they aren’t lasting in electric vehicles.
The electric vehicle 12V battery system is one that is best suited by a battery capable of tremendous cycle-life as the main design goal. The battery chemistry that suits this usage scenario best? Lithium! Lithium battery technology is specifically very good at being cycled many times and continuing to provide minimal capacity loss and degradation. This, along with reduced weight, is why these batteries are used for the high-voltage battery packs, cell-phones, laptops, medical equipment and cars where batteries are being cycled frequently and longevity is important.
Editor’s note: This post was submitted into our network by Tesla Model S owner Sean Scherer. Having suffered an unfortunate incident in his Model S that left him stranded because of a faulty 12V battery, Sherer began on a mission to create a lithium-ion based 12V battery solution that was not only more reliable than the traditional lead acid battery, but better suited for the demands of a Tesla Model S, Model X, and electric vehicles in general. He began BattMobile Batteries, who have made it their mission to improve adoption of electric vehicles by solving some of the small details that has been missed by EV manufacturers.
We’ve also included a video tutorial on how to replace the Model S 12V battery.
News
Tesla Robotaxi’s biggest rival sends latest statement with big expansion
The new expanded geofence now covers a broader region of Austin and its metropolitan areas, extended south to Manchaca and north beyond US-183.
Tesla Robotaxi’s biggest rival sent its latest statement earlier this month by making a big expansion to its geofence, pushing the limits up by over 50 percent and nearing Tesla’s size.
Waymo announced earlier this month that it was expanding its geofence in Austin by slightly over 50 percent, now servicing an area of 140 square miles, over the previous 90 square miles that it has been operating in since July 2025.
Tesla CEO Elon Musk shades Waymo: ‘Never really had a chance’
The new expanded geofence now covers a broader region of Austin and its metropolitan areas, extended south to Manchaca and north beyond US-183.
These rides are fully driverless, which sets them apart from Tesla slightly. Tesla operates its Robotaxi program in Austin with a Safety Monitor in the passenger’s seat on local roads and in the driver’s seat for highway routes.
It has also tested fully driverless Robotaxi services internally in recent weeks, hoping to remove Safety Monitors in the near future, after hoping to do so by the end of 2025.
Tesla Robotaxi service area vs. Waymo’s new expansion in Austin, TX. pic.twitter.com/7cnaeiduKY
— Nic Cruz Patane (@niccruzpatane) January 13, 2026
Although Waymo’s geofence has expanded considerably, it still falls short of Tesla’s by roughly 31 square miles, as the company’s expansion back in late 2025 put it up to roughly 171 square miles.
There are several differences between the two operations apart from the size of the geofence and the fact that Waymo is able to operate autonomously.
Waymo emphasizes mature, fully autonomous operations in a denser but smaller area, while Tesla focuses on more extensive coverage and fleet scaling potential, especially with the potential release of Cybercab and a recently reached milestone of 200 Robotaxis in its fleet across Austin and the Bay Area.
However, the two companies are striving to achieve the same goal, which is expanding the availability of driverless ride-sharing options across the United States, starting with large cities like Austin and the San Francisco Bay Area. Waymo also operates in other cities, like Las Vegas, Los Angeles, Orlando, Phoenix, and Atlanta, among others.
Tesla is working to expand to more cities as well, and is hoping to launch in Miami, Houston, Phoenix, Las Vegas, and Dallas.
Elon Musk
Tesla automotive will be forgotten, but not in a bad way: investor
It’s no secret that Tesla’s automotive division has been its shining star for some time. For years, analysts and investors have focused on the next big project or vehicle release, quarterly delivery frames, and progress in self-driving cars. These have been the big categories of focus, but that will all change soon.
Entrepreneur and Angel investor Jason Calacanis believes that Tesla will one day be only a shade of how it is recognized now, as its automotive side will essentially be forgotten, but not in a bad way.
It’s no secret that Tesla’s automotive division has been its shining star for some time. For years, analysts and investors have focused on the next big project or vehicle release, quarterly delivery frames, and progress in self-driving cars. These have been the big categories of focus, but that will all change soon.
I subscribed to Tesla Full Self-Driving after four free months: here’s why
Eventually, and even now, the focus has been on real-world AI and Robotics, both through the Full Self-Driving and autonomy projects that Tesla has been working on, as well as the Optimus program, which is what Calacanis believes will be the big disruptor of the company’s automotive division.
On the All-In podcast, Calcanis revealed he had visited Tesla’s Optimus lab earlier this month, where he was able to review the Optimus Gen 3 prototype and watch teams of engineers chip away at developing what CEO Elon Musk has said will be the big product that will drive the company even further into the next few decades.
Calacanis said:
“Nobody will remember that Tesla ever made a car. They will only remember the Optimus.”
He added that Musk “is going to make a billion of those.”
Musk has stated this point himself, too. He at one point said that he predicted that “Optimus will be the biggest product of all-time by far. Nothing will even be close. I think it’ll be 10 times bigger than the next biggest product ever made.”
He has also indicated that he believes 80 percent of Tesla’s value will be Optimus.
Optimus aims to totally revolutionize the way people live, and Musk has said that working will be optional due to its presence. Tesla’s hopes for Optimus truly show a crystal clear image of the future and what could be possible with humanoid robots and AI.
News
Tesla Robotaxi fleet reaches new milestone that should expel common complaint
There have been many complaints in the eight months that the Robotaxi program has been active about ride availability, with many stating that they have been confronted with excessive wait times for a ride, as the fleet was very small at the beginning of its operation.
Tesla Robotaxi is active in both the Bay Area of California and Austin, Texas, and the fleet has reached a new milestone that should expel a common complaint: lack of availability.
It has now been confirmed by Robotaxi Tracker that the fleet of Tesla’s ride-sharing vehicles has reached 200, with 158 of those being available in the Bay Area and 42 more in Austin. Despite the program first launching in Texas, the company has more vehicles available in California.
The California area of operation is much larger than it is in Texas, and the vehicle fleet is larger because Tesla operates it differently; Safety Monitors sit in the driver’s seat in California while FSD navigates. In Texas, Safety Monitors sit in the passenger’s seat, but will switch seats when routing takes them on the highway.
Tesla has also started testing rides without any Safety Monitors internally.
Tesla Robotaxi goes driverless as Musk confirms Safety Monitor removal testing
This new milestone confronts a common complaint of Robotaxi riders in Austin and the Bay, which is vehicle availability.
There have been many complaints in the eight months that the Robotaxi program has been active about ride availability, with many stating that they have been confronted with excessive wait times for a ride, as the fleet was very small at the beginning of its operation.
I attempted to take a @robotaxi ride today from multiple different locations and time of day (from 9:00 AM to about 3:00 PM in Austin but never could do so.
I always got a “High Service Demand” message … I really hope @Tesla is about to go unsupervised and greatly plus up the… pic.twitter.com/IOUQlaqPU2
— Joe Tegtmeyer 🚀 🤠🛸😎 (@JoeTegtmeyer) November 26, 2025
With that being said, there have been some who have said wait times have improved significantly, especially in the Bay, where the fleet is much larger.
Robotaxi wait times here in Silicon Valley used to be around 15 minutes for me.
Over the past few days, they’ve been consistently under five minutes, and with scaling through the end of this year, they should drop to under two minutes. pic.twitter.com/Kbskt6lUiR
— Alternate Jones (@AlternateJones) January 6, 2026
Tesla’s approach to the Robotaxi fleet has been to prioritize safety while also gathering its footing as a ride-hailing platform.
Of course, there have been and still will be growing pains, but overall, things have gone smoothly, as there have been no major incidents that would derail the company’s ability to continue developing an effective mode of transportation for people in various cities in the U.S.
Tesla plans to expand Robotaxi to more cities this year, including Miami, Las Vegas, and Houston, among several others.
Tesla Robotaxi’s biggest rival sends latest statement with big expansion
Tesla automotive will be forgotten, but not in a bad way: investor
