Solo Development Guide

Battery Bay

The Battery Bay can be used for mounting power system accessories including high capacity batteries, tethers, fuel cells and alternative energy sources.

Mechanical Interface

The Battery Bay mechanical interface points with Solo are:

  • Battery tray interlock
  • Electrical connectors
  • Release button
  • Keep-out zones for propellers (and also other payload bays).

We recommend you enclose your power solution using the battery bay envelope, as this correctly implements the required mechanical interface points. The battery bay envelope CAD file can be downloaded from here.

Electrical Interface

The electrical interface with Solo uses the following connectors:

  • Battery side connector (female) is a Molex 171090-0048 (PDF). This is a custom connector that can only be purchased in minimum orders of 1,000 units.

  • Solo / charger side connector (male) is a Molex 171088-0048 (PDF)

The battery interface has 3 prongs with 4 contacts. The SMBus connector has 2 contacts: SCL (top) and SDA (bottom) on the top-most prong. The Battery + and - are the bottom 2 prongs. The battery and SMBus must share a common ground.

The connector contacts are rated for 40A on the power contacts.

Solo / Battery charger side male connector (Molex 171088-0048)
Figure: Solo / Battery charger side male connector (Molex 171088-0048)
Battery side female connector (Molex 171090-0048)
Figure: Battery side female connector (Molex 171090-0048)

Battery Payload Requirements

Battery bay payloads should have approximately the same physical and electrical characteristics as the current battery: Solo Battery Specifications.


The recommended physical characteristics are:

  • 500 grams
  • Operating Temp: 0C ~ 40C
  • Discharging operating temp: -20C ~ 60C

Changing the battery weight will have a corresponding impact on the weight available for accessories. The center of gravity must remain close to the current location.


The main physical characteristics are:

  • Operating voltage range: 16.8 V to 12.0 V
  • 15A draw during hover with no payload (no Gimbal/Camera or other acessories)
  • 20A draw during hover with full 700g payload
  • 120A maximum burst (depends on wind, payload, and maneuver)

Battery Safety Features

It is up to the power system manufacturer to make sure all safety and regulatory certifications (including UL) are obtained. The power system must not have a low-voltage or low-capacity cut-off.

Communication Protocol

Solo uses the standard SMBUS spec for communicating with the battery. To interface with the battery it is best to implement the full specification.