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Overnight-charging high-energy system for all-electric and hybrid heavy vehicles




Integrated to our high-energy ZEN range, the ZEN 35 is an overnight-charging battery pack for all-electric and hybrid heavy vehicles.

The ZEN 35 battery pack is a 34.9 kWh modular system whose mechanical design has been optimized for for bus’roof and back integration

Its very good energy density of 125 Wh/kg allows the vehicles to travel all day without being recharged.The battery charges during the night at the depot.

Full day operations

Great energy density of 125 Wh/kg

Scalable modular system

34.9 kWh packs connected in parallel

Optimal mechanical design

For bus' roof & back integration

e.City Gold from CaetanosBus run with Forsee Power’s ZEN 35 technology

Since 2020, ZEN 35 battery pack is running in London equipping 34 buses of the Portuguese manufacturer CaetanoBus.

Forsee Power engineering teams have integrated on e.City Gold vehicles’ roof 350 kWh of  energy allowing them to reach 230 km of autonomy without charging during operations. The bus is able to fully charge the high-energy ZEN 35 batteries during the night at the depot.

Heuliez Bus integrates ZEN 35 technologies for RATP

As part of the biggest European electric bus tender lead by RATP, Forsee Power equips more than 260 bus from the French manufacturer, Heuliez Bus, with ZEN 35 battery systems.

In July 2021 , we have won with our partner IVECO the largest batch in the call for tenders launched by RATP as part of its Bus2025 plan.  Forsee Power will equip 180 standard  GX 337 ELEC buses of HEULIEZ with the brand-new ZEN 42, a high-energy battery system that provides 20% more energy density than the ZEN 35, in the same format.

This call for tenders, funded by Île-de-France Mobilités, are part of the implementation of the Bus2025 plan aimed at making the Paris bus fleet and its region more environment friendly.


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