The U.S. aircraft register, updated daily
Special conditions · electric or hybrid design · aircraft

Special Conditions: AeroMech, Incorporated; Hawker Beechcraft Corporation, Model B200 and Other Aircraft Listed in Table 1, Approved Model List (AML); Installation of MD835 Lithium Ion Battery

Special conditions are rules the FAA writes for one design when the standard certification rules do not cover something new about it. These were published August 19, 2010 for Aeromech INC. System: electric propulsion.

What it applies to

Applicant
Aeromech INC
Makes
AeroMech Inc.
Models
—
Published
August 19, 2010
Effective
August 8, 2010
The FAA's document
On the FAA's site

The FAA's summary their words, unchanged

These special conditions are issued for the AeroMech, Incorporated; Hawker Beechcraft Corporation, model B200 and other part 23 aircraft listed on the AML. These airplanes as modified by AeroMech, Incorporated will have a novel or unusual design feature(s) associated with installation of the Mid-Continent Instruments MD835 Lithium Ion (Li-ion) battery. The applicable airworthiness regulations do not contain adequate or appropriate safety standards for this design feature. These special conditions contain the additional safety standards that the Administrator considers necessary to establish a level of safety equivalent to that established by the existing airworthiness standards.

Source: FAA special conditions (final) from the Dynamic Regulatory System; the Federal Register carries the same notices.