Quick-boosting supercapacitor powers battery-free ebike

In the realm of urban transportation, the Pi-Pop ebike emerges as a noteworthy contender, especially for those seeking a sustainable and efficient means of commuting. This French-designed ebike deviates from the conventional path, opting for a supercapacitor-powered system instead of the traditional battery pack. This article delves into the mechanics, advantages, and limitations of the Pi-Pop battery-free supercapacitor ebike, providing a comprehensive overview for potential urban commuters.

At first glance, the Pi-Pop ebike resembles a basic urban ebike-sharing platform, with its step-through design and unassuming appearance. However, this façade belies the innovative electric-assist system within. The bike utilizes a supercapacitor-boosted system, a notable departure from the battery packs ubiquitous in most ebikes. This system is designed to harvest energy during flat and downhill rides, which is then used to provide pedal-assist power on uphill routes.

Pi-Pop’s journey toward creating a clean, sustainable option for urban bicycle commuting has been marked by continuous innovation. Over the past two years, it has launched three generations of battery-free supercapacitor ebikes and experimented with a compact, chain-free ebike system. The latest, the third-generation model, introduced in mid-2023, includes several evolutionary improvements. These enhancements encompass a torque sensor, suspension fork, and an updated set of components.

The Pi-Pop’s supercapacitor continuously charges and discharges during the ride, unlike a battery that depletes after a set distance. Images courtesy Pi-Pop

The core of Pi-Pop’s design lies in its unique energy storage and dispensation mechanism. Unlike traditional ebikes, which require grid hookups for charging, the Pi-Pop bike captures energy from the rider’s pedaling and regenerative braking. This energy is then converted into electricity and stored in supercapacitors located alongside the rear rack. The system is fine-tuned to minimize impact during flat rides, increasing energy generation on downhills and peaking during active braking.

When the rider begins pedaling uphill, the stored electricity is immediately discharged, providing up to 250 watts of pedal assistance. This process, managed by sensors, ensures an automatic and seamless transition through various terrains.

Supercapacitor boxes may not be lighter or smaller than a typical ebike battery, but they offer different benefits.

Interestingly, the elimination of a conventional battery pack does not significantly reduce the bike’s weight. The Pi-Pop ebike weighs in at 48 pounds (21.7 kg), and its supercapacitor boxes do not offer a sleeker profile compared to modern battery packs. However, the design prioritizes other benefits. The supercapacitors, free from the sensitive materials found in lithium batteries, utilize basic materials like aluminum, carbon, cellulose, and polymer. They boast an impressive estimated lifecycle of 10 to 15 years and are largely recyclable.

One of the most appealing aspects of the Pi-Pop ebike is its independence from the grid. It is always ready to ride, charging its motor power during the ride itself. However, the supercapacitors do have a gradual drain if left unused, potentially requiring a pre-charge lap after extended periods of non-use.

Pi-Pop integrates wires from its supercapacitors internally, running them through the bike’s frame.

The Pi-Pop ebike does have its limitations. Its supercapacitors can store only small amounts of energy, which means the system will deplete its power on longer or steeper inclines beyond a 10% grade over a distance of approximately 1,640 feet (500 meters). At this point, the electric assistance will gradually diminish, leaving the rider to pedal a heavy, non-electric bike. Consequently, Pi-Pop markets this ebike primarily to urban riders facing modest hills rather than those looking to navigate challenging terrains like the French Alps.

In terms of production and availability, Pi-Pop assembles about 100 bikes monthly at its headquarters in Orléans, France. With plans to increase production tenfold by 2024, the company aims for a broader European expansion. The third-generation Pi-Pop battery-free supercapacitor ebike is currently priced at €2,450 (approximately US$2,680), including VAT.

Colorful display shows power and speed.

Source: Pi-Pop

1 thought on “Quick-boosting supercapacitor powers battery-free ebike”

Leave a Comment