If you are buying an electric tricycle or a low-speed four-wheeler, or considering swapping lead-acid batteries for lithium ones, don't rush to pay. Ask yourself these three questions first—it could save you a lot of wasted money.

Question 1: How far do I actually travel each day?

This is the most critical factor. Many people fall into the trap of thinking "bigger is better" when buying batteries. However, every 10Ah increase in capacity adds hundreds of yuan to the price.

Under 20 km/day: 48V 32Ah is sufficient; don't overspend.

50–80 km/day: 60V 40–60Ah is the "sweet spot" (mainstream choice).

Over 100 km/day, or frequent hill climbing/heavy loads: Go straight for at least 72V 100Ah.

Let's do the math: At a rate of 0.5 yuan per Wh, a 60V 40Ah battery (2.4 kWh) costs roughly 1,200–1,500 yuan, whereas a 60V 100Ah battery (6 kWh) costs 3,000–3,500 yuan. The extra cost alone would cover years of charging.

Question 2: Is my vehicle compatible with lithium batteries?

Not every vehicle can simply switch to lithium batteries. Focus on two key points:

Controller voltage tolerance: After switching to lithium, the fully charged voltage is higher than that of lead-acid batteries (e.g., a 60V lead-acid battery peaks at around 58V, while a lithium one hits 67.2V). Older controllers may burn out if they lack sufficient voltage tolerance; have a technician measure this before swapping.

Battery compartment dimensions: Lead-acid batteries are bulky and heavy, while lithium batteries are much more compact, but the shape of the compartment might not match. Measure the length, width, and height before buying—don't just assume you can "squeeze it in."

Question 3: Who handles after-sales service?

This is where people most often run into trouble. If a passenger car battery fails, you go to the dealership, but if an electric tricycle's lithium battery breaks, you will likely have to find someone to repair it yourself. Confirm three things before buying:

 Does the seller have a local service center? (Ideally, one within the county.)

What are the warranty periods for the battery cells and the BMS? (Industry standards: 5 years or 3,000 cycles for cells; 2–3 years for the BMS.)

If a fault occurs, is it repaired or is the entire pack replaced? (With some smaller manufacturers, a pack failure means the whole unit has to be discarded.)

In short: choose the capacity based on your mileage needs, verify that it fits your vehicle, and clarify the after-sales service terms. Get these three things right, and you’re unlikely to make a mistake.