Servers by jDrones

Intelligent flight battery

battery

(Andreas) #1

Hy

I’m still looking around for intelligent flight batteries in the 6s range but apparently there are
no other options then the DJI ones. However we still can’t readout the I2C port of those batteries
or does some one has different informations?
Are there other 6s intelligent flight batteries available?

Andy


(Andre-K) #2

http://ardupilot.org/copter/docs/common-smart-battery.html

Only Solo and Maxell so far. DJI is no-no , way to closed, proprietary, and ready to sabotage you at next firmware update, also pricing is not exactly attractive.


(Andreas) #3

solo is only 4s and from the Maxell battery I havent seen them since they were announced a while back…


(Muhammad Al-Rawi) #4

Hi Andreas,

I popped open a busted Inspire 1 battery earlier this year and found it has the TI BQ78350 and BQ76930 battery management chipset which supports SMBUS. You can see these, as well as two test points labeled “SMBD” and SMBC" near the BQ78350 in the image of the PCB here: http://i.imgur.com/bjeAfxz.jpg

The bus then goes to an MSP430 which seems to be connected to the two pads on the battery’s connector (through opto-isolators if I remember correctly). It’s Probably translating the SMBUS into some proprietary protocol DJI uses (I didn’t have a scope or logic analyzer at the time so I can’t say for sure).

If you really want to use Inspire 1 batteries with SMBUS, you might try disconnecting the external data pins from the MSP430 and running them directly to the SMBUS test points near the BQ78350. There are two jumper links to the right of the test pads that you will need to break to disconnect the MSP430 from the BQ78350.

I don’t know if I can get that battery back as it belongs to the local university, but if I can I’ll give this a try. Won’t be any time soon, however.


(Andreas) #5

hmm ok thx for the reply!
So it seems “easier” to build our own intelligent flight battery…

Andy


(Federico mari ) #6

I have disassembled the batteries of Inspire 1 (TB-47) and Inspire 2 (TB-50) and connected a logic analyser to sniff the communication between the drone and the battery…
If anyone is interested on working out the communication protocol, feel free to ask me for the logic data I sampled.


(MRricci) #7

We have developed a prototype battery management board that is capable of 6s through 12s battery packs.
It measures all of the cell voltages as well as the pack terminal voltage and current; and reports them via a CANbus protocol that is compatible with the Pixhawk CAN interface. It also integrates current versus time to do fuel gauging as well. We are working on modifying Arducopter to be able to read the cell/pack voltages via CAN and (eventually) log or report them back via MAVLINK telemetry. The BMS hardware and CAN interface is built, tested, and working; the Arducopter software end still needs significant work. Please contact me if you are interested in possibly being a development partner and helping us to prove out our technology prior to a product launch.


(minmin) #8

I just know TATTU has 18000 6s smart battery, but I don’t know if can use on yours.


(Anton K) #9

Hello Naish I’d like to analyze the protocol


(Evan Williams) #10

mrricci,

Might I ask if you’ve more information on said product?
Or where the development currently stands?


(MRricci) #11

Hi Evan,
We have manufactured a handful of prototype boards and bench tested them and flown them on our hybrid multirotor. https://www.youtube.com/watch?v=0_0dwSnuOYw

The board communicates with our Hybrid-Electric gen-set via CAN bus, and also makes all the battery information available to the Pixhawk flight controller via the CAN bus. The Pixhawk code to read the CAN message has not yet been completed, but should be fairly straightforward for a Pixhawk developer with CAN communications experience.

Since we are building them in only small quantities right now they are fairly expensive (>$1000 each), and are not really available as a “product” since we can’t support them on a one-off basis. We are interested in working with partners who would have a need for multiple units eventually in which case we can provide partner support to get a unit working for an application that may go to higher volume. We can also license the design and software to interested 3rd parties as well.

Functions:

• Monitors all cells for over/under voltage
• Monitors pack temperature
• Monitors PCB temperature
• Monitors pack current and pack voltage

• Implements fuel gauge function for pack

• Provides pack status and monitoring information to Flight Controller
• Alerts Hybrid controller and Flight controller of pack warning and alarm conditions
• Manages in-flight recharging of pack by sending charging requests to LaunchPoint Hybrid System gen-set controller

• Controls optional battery disconnect protection switch

Features:

• CAN communications interface to flight controller and hybrid power system controller
• Broadcasts warnings and alarms as battery condition nears limits and then exceeds safety limits
• If optional disconnect switch is integrated can disconnect battery pack as required for safety and pack protection
• Input connections for two thermistor battery pack temperature sensors
• Configured for 6s, 7s, and 12s cell count packs
• Additional units can be daisy chained for higher cell count battery packs

Specifications:

Connectors on PCB for 6s, 7s, and 12s battery packs

Rated 70A peak and 55A continuous current output

Weight: 50 gram


(Federico mari ) #12

Hi Anton,
Send me a PM with your mail address and I will give you the Logs.
I’m also keen to pay some $$ to whoever can crack this up!


(Anton K) #13

It appears there’s nothing to crack. There’s UART connection 115200-N-1. There’s even a dissector for protocol analysis in wireshark: https://github.com/o-gs/dji-firmware-tools/tree/master/comm_dissector


(Anton K) #14

Sorry for being misleading, previously I was speaking about BT-50 for DJI Inspire 2 Smart Battery, it’s UART. But it’s nothing to do about Intelligent flight batteries like PH4 batteries for DJI Phantom 4. So it’s still actual to parse the Intelligent flight battery sniffs. By the way there’s no private message feature on this forum…


(Federico mari ) #15

DJI-Smart_batt.zip (525.2 KB)
Hi Anton,
I have attached the logs from the TB-50 and TB-47 smart battery.


(Mark Gil E. Luy) #16

Hi guys,

I’m a newbie in the rc world and still learning and i would like to ask is there a way to build my own intelligent 11.1V battery for my SJRC F11 DRONE…?

Thank you