How to justify the cost of Lithium when Lead Acid is so much cheaper?
One of the most common topics that we see on Facebook groups & forums is the question:
How can you justify the cost of LiFePO4 versus Lead Acid?
So in this article, we’re going to be covering this topic to shed some light on the numbers and to prove how good value for money LiFePO4 is!
Firstly, we’ll say that the chemistry of the battery system that you choose should be driven by two main things:
What are your current needs?
Do you think your needs will change in the future?
By needs, we mean what do you need to draw from your battery or run on it? Do you just need to run lights in your van, charge your phone and maybe charge a laptop? Do you need to run a large inverter that can run an induction cooktop, Nespresso machine and TV & PS4?
OK, let’s settle in. Time to bring out the calculator.
This is a serious mouthful! But … fair is fair and we needed to give you all the facts and figures.
When people compare Lithium with Lead Acid generally they are talking about LiFePO4, and for Lead Acid, they could be talking about FLA (flooded lead acid) or AGM. So let's talk about LiFePO4 and Lead Acid.
The big issue regarding LiFePO4 is whether or not you need to upgrade your charging equipment. From our experience, you see someone extolling the virtues of LiFePO4, but very often they do not mention the fact that you may need to change your charging systems. We hate seeing people spend a whole heap of cash on a new LiFePO4 battery and then they discover that they also need to replace all their chargers. In some cases, this can be the same cost as the battery itself. Let’s see how this affects your decision.
The question becomes, are you looking at the initial cost of the installation ONLY, or are you looking longer term? If you’re really tight for cash NOW, AND you have equipment not suitable for LiFePO4 then good old Lead Acid may be for you. If you have a little leeway on your budget and you’re thinking longer-term or you’re a heavy power user then you may want to consider LiFePO4.
So let’s talk through the figures.
If you’re DIY-ing a 280ah or 272ah LiFePO4 battery and you’re sourcing cells and BMS from a reputable local supplier then you can expect your battery to cost around $1100. This is based on roughly $200 per cell, $200 for the BMS and a few odds and ends. If you’re buying a pre-assembled or manufactured battery from a reputable local supplier expect to pay around $1500 to $2500. If you go the cheapest possible route you can get away with really cheap cells at around $400, and add a good quality BMS at around another $140. Unless you can borrow a desktop charger to do the top-balancing you’d need to get one for around $60.
So:
$1080 for the battery
$460 to upgrade your equipment if it’s too outdated
That’s nearly 4x more expensive than Lead Acid at $400, or at least 2.7x if you don’t need to upgrade your equipment.
If you are able to go the cheapest route this ratio drops to 1.5x
Why would you still consider LiFePO4?
If you’re making a long-term investment then your LiFePO4 battery will last 10x longer than Lead Acid.
Does that really matter?
Depends on how often you’d use your van. Depends on how long you plan to keep your van. Depends on whether you’re a heavy power user or not. Depends if this is a long term investment that, should you sell your van, that you’d take your expensive battery with you (selling it with a cheap Lead Acid installed).
The thing is, a LiFePO4 solution will in theory last your lifetime. If you’re an average camper and only do two cycles per week, for example, the expected 3000 cycles will last 30 years. And there are ways to extend the 3000 cycles to around 3500 or even 4000 cycles. Imagine knowing your battery will still be OK in 40 years time!
On the other hand, quite a number of people say they don’t care about the long term, particularly as they believe that new technology is just around the corner and will become cheaper and cheaper anyway. They’re probably right.
It all depends if you’re looking at longer-term cost per cycle or short term total installation cost.
Then there are a few “soft” factors.
The weight difference is enormous. If you have a limited payload you really should consider moving off anything with lead. Definitely NOT Lead Carbon!
The space difference is also substantial. A single LiFePO4 battery will take up much less space than 4x Lead Acid batteries that will give you the same performance.
Recent tests and comparisons show that the 50% stated “usable” capacity of Lead Acid is not actually correct, it is in reality closer to 40%. We have found this to be true.
Personal experience. We have yet to meet someone that regretted their LiFePO4 investment. Power is so important these days, why spend thousands on everything else and skimp on one of the most important things. Lithium simply works better than lead.
If you’d like to see the spreadsheet with the calculations on it that we referenced above, you can see it here.
