Lead vs Lithium Batteries: To Spec
Technology never stops evolving. Battery technology especially doesn't stop evolving, as humanity's power needs never stop growing. We always need bigger batteries with better charge capacities, and that's no different in cars either. Usually these improvements come from more efficient chemical reactions inside the battery.
Lead and Lithium batteries are the two most common types of batteries that you’ll find in vehicles today. We’re going to go over some of their respective characteristics, and why sometimes you want a lead battery, but other times you might want a lithium batter.
Did you know? Lead-acid batteries were the first rechargeable battery ever invented, in 1859 by French physicist Gaston Plante. These are the same types of batteries most people use in their cars. Lead-acid is cheap and effective, the magic formula for mass adoption. Their discharge efficiency isn’t great, but they work well in cars since vehicle engines also use alternators that recharge the battery when driven. Thus there’s little risk of depleting a lead car battery while it’s in use (until it’s old, at least), but actually a high risk of depleting them while the vehicle power is on yet the engine is not. Anyone who’s killed their engine while blasting music for a public gathering has probably learned this fact the hard way…
Lithium is a newer battery technology, especially popular in electric cars like Tesla Cyborg-trucks or whatever that box-mobile was called. It’s more expensive and frankly a little more dangerous under certain applications since they’re harder to extinguish in a fire, but their capacity under use isn’t diminished as quickly as lead-acid. This means they tend to last longer and actually offer higher price-performance ratios, if one can afford the initial cost. Lithium is especially practical in vehicles with lots of electronic components with variable discharge rates, as they do not drain lithium as quickly as they drain lead.
DIFFERENCES IN SPECIFICATIONS
Here is a helpful chart that compares the most important performance specifications of Lithium against SLA (sealed lead acid) batteries. This chart was made by Power-Sonic, one of the leading battery manufacturers in the US.
As Power-Sonic states on their blog, “the most notable difference between lithium iron phosphate and lead acid is the fact that the lithium battery capacity is independent of the discharge rate.” What this means is that with lithium, how much energy the battery stores remains the same regardless how much energy is being drawn from it. By contrast, if you use a lead battery at a high discharge rate (high power draw), the capacity will decrease faster, and you’ll run out of juice quicker.
If it helps, think of lead and lithium as two people exercising. Both intend to work out for an hour. If lead works out lightly then lead will make it the whole hour. But if lead works out extra hard, it won’t make it the whole hour. Lithium, on the other hand, will last the entire hour whether it’s working hard or not. It’s a crude comparison but hopefully makes a little sense. If not, feel free to read on C-rates on this page from Battery University:
What does this mean for trucks and cars? It essentially means you can rely on the lithium battery for longer; your battery is less likely to die suddenly. Also, it’ll probably last longer as far as the warranty is concerned too.
Which One for Me?
For most applications, a standard SLA lead battery is more than enough. There's good reason this tech has been in use for decades and still is.
While lithium is more expensive, generally it’s more than worth the cost due to extended reliability. For newer cars, we urge customers to invest in lithium batteries, but in almost all cases, lead batteries truly are more than enough for the job. For what it’s worth though, a new lead battery and a new lithium battery- with no manufacturing defects- are effectively equivalent under normal usage conditions. You have to be running careful tests to even see the difference. Most people don’t need to worry about the difference, too much.
Need battery repair service? Is your battery dying randomly? Just want to replace your battery without getting your hands dirty? Just give Tedious Repairs a call and we’ll be more than happy to handle all your battery service needs!