November 16, 2022

As a provider of electrified power solutions, Cummins regularly receives questions on technologies facilitating the adoption of electric vehicles. One question that often comes up is ‘what is the difference between lead acid and lithium ion, and when should each battery type be used?’

Here are the top 3 differences between the two battery chemistries and some examples of which technology to opt for when going electric.

Lithium ion vs Lead acid battery
Full size infographic featured at the end of the article.

1. Cost
This is usually the subject at the forefront of everyone’s minds and a key driver for deciding ‘what is the right product for my fleet?’. As is often the case, it is not a simple answer and cost effectiveness is really dependent on the needs of your application. Lead acid is a popular cost-effective battery chemistry, available in large quantities with little worries relating to security of the supply and in a variety of off the shelf pack sizes. Lead acid is great fit for large scale stationary applications where space is abundant and energy requirements are low. However, when you start looking at price in terms of the power or range, lithium ion technology can often be a more favorable option.

2. Energy and Range
Comparing the two chemistries side-by-side, lithium ion achieves an energy density of 125-600+ Wh/L versus 50-90 Wh/L for lead acid batteries. In other words, if you were to drive the same distance using each type of batteries in an identical vehicle, the lead acid battery could take up to 10 times the volume that the lithium ion would, and it’s also heavier. Therefore, using lithium ion batteries allows space for other important payloads, for example, more passengers in a bus or more parcels in an electric delivery truck. A high energy density also affords the vehicle a much longer range, meaning the user does not need to charge as often when powered by lithium ion technologies.

3. Charging
Charging a lead-acid battery can take more than 10 hours, whereas lithium ion batteries can take from 3 hours to as little as a few minutes to charge, depending on the size of the battery. Lithium ion chemistries can accept a faster rate of current, charging quicker than batteries made with lead acid. This is critical for time-sensitive applications where vehicles have high utilization and fewer break intervals. In the case of a terminal tractor, every minute that the ship is docked at the port has financial repercussions on the fleet owner, so the battery must be charged quickly during breaks to load the ship.

There is no one-size-fits-all approach to batteries, rather, it is about providing the right electric solution to meet the needs of the application. Cummins designs and sells flexible, scalable lithium ion batteries as a prime source of power for commercial vehicles, and other mobile and stationary applications.

Learn more about how Cummins is leading the charge in electrification with its lithium ion battery portfolio and more news about electrified power.