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Why Tesla’s lead acid 12V battery needs to be lithium-ion based

Published

9 years ago

September 22, 2016

Teslarati

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.

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Tesla cleared in Canada EV rebate investigation

Tesla has been cleared in an investigation into the company’s staggering number of EV rebate claims in Canada in January.

Published

7 hours ago

July 11, 2025

Zachary Visconti

Credit: Tesla

Canadian officials have cleared Tesla following an investigation into a large number of claims submitted to the country’s electric vehicle (EV) rebates earlier this year.

Transport Canada has ruled that there was no evidence of fraud after Tesla submitted 8,653 EV rebate claims for the country’s Incentives for Zero-Emission Vehicles (iZEV) program, as detailed in a report on Friday from The Globe and Mail. Despite the huge number of claims, Canadian authorities have found that the figure represented vehicles that had been delivered prior to the submission deadline for the program.

According to Transport Minister Chrystia Freeland, the claims “were determined to legitimately represent cars sold before January 12,” which was the final day for OEMs to submit these claims before the government suspended the program.

Upon initial reporting of the Tesla claims submitted in January, it was estimated that they were valued at around $43 million. In March, Freeland and Transport Canada opened the investigation into Tesla, noting that they would be freezing the rebate payments until the claims were found to be valid.

READ MORE ON ELECTRIC VEHICLES: EVs getting cleaner more quickly than expected in Europe: study

Huw Williams, Canadian Automobile Dealers Association Public Affairs Director, accepted the results of the investigation, while also questioning how Tesla knew to submit the claims that weekend, just before the program ran out.

“I think there’s a larger question as to how Tesla knew to run those through on that weekend,” Williams said. “It doesn’t appear to me that we have an investigation into any communication between Transport Canada and Tesla, between officials who may have shared information inappropriately.”

Tesla sales have been down in Canada for the first half of this year, amidst turmoil between the country and the Trump administration’s tariffs. Although Elon Musk has since stepped back from his role with the administration, a number of companies and officials in Canada were calling for a boycott of Tesla’s vehicles earlier this year, due in part to his association with Trump.

Tesla excluded from incentives in Canada over Trump tariffs

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Tesla Semis to get 18 new Megachargers at this PepsiCo plant

PepsiCo is set to add more Tesla Semi Megachargers, this time at a facility in North Carolina.

Published

7 hours ago

July 11, 2025

Zachary Visconti

Credit: Tesla

Tesla partner PepsiCo is set to build new Semi charging stations at one of its manufacturing sites, as revealed in new permitting plans shared this week.

On Friday, Tesla charging station scout MarcoRP shared plans on X for 18 Semi Megacharging stalls at PepsiCo’s facility in Charlotte, North Carolina, coming as the latest update plans for the company’s increasingly electrified fleet. The stalls are set to be built side by side, along with three Tesla Megapack grid-scale battery systems.

The plans also note the faster charging speeds for the chargers, which can charge the Class 8 Semi at speeds of up to 1MW. Tesla says that the speed can charge the Semi back to roughly 70 percent in around 30 minutes.

You can see the site plans for the PepsiCo North Carolina Megacharger below.

Credit: PepsiCo (via MarcoRPi1 on X)

Credit: PepsiCo (via MarcoRPi1 on X)

READ MORE ON THE TESLA SEMI: Tesla to build Semi Megacharger station in Southern California

PepsiCo’s Tesla Semi fleet, other Megachargers, and initial tests and deliveries

PepsiCo was the first external customer to take delivery of Tesla’s Semis back in 2023, starting with just an initial order of 15. Since then, the company has continued to expand the fleet, recently taking delivery of an additional 50 units in California. The PepsiCo fleet was up to around 86 units as of last year, according to statements from Semi Senior Manager Dan Priestley.

Additionally, the company has similar Megachargers at its facilities in Modesto, Sacramento, and Fresno, California, and Tesla also submitted plans for approval to build 12 new Megacharging stalls in Los Angeles County.

Over the past couple of years, Tesla has also been delivering the electric Class 8 units to a number of other companies for pilot programs, and Priestley shared some results from PepsiCo’s initial Semi tests last year. Notably, the executive spoke with a handful of PepsiCo workers who said they really liked the Semi and wouldn’t plan on going back to diesel trucks.

The company is also nearing completion of a higher-volume Semi plant at its Gigafactory in Nevada, which is expected to eventually have an annual production capacity of 50,000 Semi units.

Tesla executive teases plan to further electrify supply chain

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Tesla sales soar in Norway with new Model Y leading the charge

Tesla recorded a 54% year-over-year jump in new vehicle registrations in June.

Published

12 hours ago

July 11, 2025

Simon Alvarez

Credit: Tesla

Tesla is seeing strong momentum in Norway, with sales of the new Model Y helping the company maintain dominance in one of the world’s most electric vehicle-friendly markets.

Model Y upgrades and consumer preferences

According to the Norwegian Road Federation (OFV), Tesla recorded a 54% year-over-year jump in new vehicle registrations in June. The Model Y led the charge, posting a 115% increase compared to the same period last year. Tesla Norway’s growth was even more notable in May, with sales surging a whopping 213%, as noted in a CNBC report.

Christina Bu, secretary general of the Norwegian EV Association (NEVA), stated that Tesla’s strong market performance was partly due to the updated Model Y, which is really just a good car, period.

“I think it just has to do with the fact that they deliver a car which has quite a lot of value for money and is what Norwegians need. What Norwegians need, a large luggage space, all wheel drive, and a tow hitch, high ground clearance as well. In addition, quite good digital solutions which people have gotten used to, and also a charging network,” she said.

Tesla in Europe

Tesla’s success in Norway is supported by long-standing government incentives for EV adoption, including exemptions from VAT, road toll discounts, and access to bus lanes. Public and home charging infrastructure is also widely available, making the EV ownership experience in the country very convenient.

Tesla’s performance in Europe is still a mixed bag, with markets like Germany and France still seeing declines in recent months. In areas such as Norway, Spain, and Portugal, however, Tesla’s new car registrations are rising. Spain’s sales rose 61% and Portugal’s sales rose 7% last month. This suggests that regional demand may be stabilizing or rebounding in pockets of Europe.