Nearly every electric dumper and cargo tricycle leaves the factory with lead-acid batteries, because that keeps the headline price low. Lithium iron phosphate (LiFePO4) is offered as an upgrade. Here is when the upgrade pays.
The straightforward case for lead-acid
- Lowest upfront price — often the difference between a sample order and no order
- Simple to charge and to replace almost anywhere in the world
- Tolerant of being left partly charged for a few months
- Adequate for machines used a few times a week
The straightforward case for LiFePO4
- Roughly three times the cycle life of lead-acid in real service
- About one third of the weight for the same capacity — on a 129 kg machine that is significant
- Holds voltage far better in cold weather — lead-acid can lose half its usable capacity near freezing
- Charges in a fraction of the time, and can be opportunity-charged during breaks
- No acid, no gassing, and no need for ventilation when charging indoors
The calculation
If you replace a lead-acid pack every two years at a certain price, and a LiFePO4 pack costs 30–50% more but lasts six years, the lithium pack is cheaper on a per-year basis from the first replacement onward — and it saves the labour of the swap. The older the machine gets, the further ahead lithium is.
The exception is a machine that will be lightly used, or one being bought as a sample. There, lead-acid keeps the initial outlay down and the machine can always be upgraded later.
What to insist on
Whatever chemistry you choose, insist on a battery management system with the lithium pack, a charger with float protection for lead-acid, and no inflated runtime claims. A 24 V system advertised at five working hours is often two to three in practice. Ask for the capacity in watt-hours (V × Ah) rather than a claimed number of hours — it is the number you can compare.
A note on shipping
Both chemistries are classified as dangerous goods for sea freight. Lithium is typically UN3480 or UN3481, lead-acid UN2794. This does not prevent shipping, but it changes the freight rate, the documentation and sometimes the port you can sail from. Allow for it in your costing from the beginning rather than discovering it at booking.