The first track test for the 2018/19 Formula E car is set to take place in October, but teams will have to wait longer than expected for their first runs.
From the 2018/19 season onwards the Formula E car, built by Spark Racing Technologies and powered by a 54kWh McLaren Applied Technologies (MAT) battery, will need to last an entire race distance, moving the series away from mid-race car swaps.
Spark will coordinate the October test, which is slightly behind schedule as a result of the extra time taken last summer to decide on a battery supplier.
Originally the FIA wanted to 'make available one full product package to each car manufacturer by 1st October 2017'.
The chassis crash test is scheduled for September 1 and the first group test session, involving all teams, has also been pencilled in for February 2018.
Last month, the nine registered manufacturers received initial technical information from MAT, which is the project lead in ensuring all battery system requirements and integration.
The car is scheduled to be homologated in August 2018.
Among the changes for the 2018/19 season is a peak power hike from 200kW to 250kW, with energy harvesting also rising to the same amount.
The new car is currently due to weigh 930kg, 42kg heavier than what was initially pursued.
Part of the reason for this is a heavier-than-expected MAT battery, which one team's technical director claimed "would be nearer 350-360kg [excluding safety structure] with 209 cells".
The current Williams Advanced Engineering battery is made from five modules of 33 cells, making 165 in total.
Spark is believed to be adapting new materials to the chassis, including 3D printed parts, to compensate for the heavier battery.
Autosport has also learned current battery supplier Williams Advanced Engineering has conducted a full simulated characterisation duty-cycle test on a module of battery cells.
The results of this test are believed to have shown degradation in performance of the battery pack by up to 10% over the targeted duty cycle of the 2018/19 season.
This would essentially mean that the battery would not last at the levels needed to run a single car for the full campaign.
The FIA is believed to have approached MAT about this, and the supplier reported it has already moved to address this discrepancy.
MAT is expected to make plans for a reduction in the rate of charge that will affect the battery life substantially.
It is using Sony Energy Devices-derived cells for the battery, while US-based company Atieva will design, develop and manufacture the battery packs.
The industrial process of ensuring that the 2018/19 battery provides the necessary range for a one-car-per-driver race is ongoing between MAT and the FIA, which is believed to be continuing to use a team of independent specialists.
This is under the control and consultation of Professor Burkhard Goeschel, the president of the Electric and New Energies Championships Commission.