Waiting for the BattGO standard to become more popular got myself one of the BG-Linker devices, that allow to connect your BattGO compatible batteries to PC via USB to read battery parameters and set some user preferences (such as e.g. the self discharge time).



To do so you use a PC app



Of course I had to look inside, and it is based on the GigaDevice GD32f150G8U6 MCU (datasheet HERE)



The chip converts the BattGO proprietary, encrypted communication protocol with the battery into a bunch of serial commands exchanged between the dongle and the PC (at 115200 baud) which have the following format:
&<COMMAND> <DATA><LF> (where <LF> is the line feed character - 0x0A)

The response format is similar:
%<COMMAND> <DATA><LF>

The full list of commands can be retrieved after typing &HELP<LF> (I've added comment to some of some commands below)

&TEST<LF> - check if dongle connected
&CBL<LF> - check if battery connected
&UPD<LF> - probably used to enter firmware update mode
&CUH<LF>
&CDS<LF>
&CSI<LF> - returns battery serial number
&UHC<LF>
&UPC<LF> - returns user parameters (e.g.  auto-discharge time)
&UVC<LF> - returns current battery state (e.g. cell voltage, temperature, etc.)
&UPW<LF> - sets user parameters
&RLI<LF>
&RLE<LF>
&RMC<LF>
&CBR<LF> - returns serial number (divided into 4 groups) and manufacturer name
&CPR<LF> - returns battery physical parameters (e.g. type, capacity, number of cells, etc.)
&HELP<LF> - returns the list of available commands

The communication between the dongle and the battery is done at 9600 baud using one wire serial but is unfortunately encrypted. The structure of the messages is the following:

AA SR TR LN DATA CS

where:
AA - one byte message header (when not a header but part of the actual data it is duplicated - AA AA)
SR - most likely one byte determining the message source (messages from the dongle have 0x01 here, messages from the battery have 0x02 here)
TR - most likely one byte determining the message target (messages to the dongle have 0x01 here, messages to the battery have 0x02 here)
LN - data length in bytes (note that duplicated AAs are not counted
DATA - bytes of encrypted data
CS - two bytes of the checksum, which is the sum of all the message bytes (except the AA header and the CS itself of course) written in little endian

Here are some example messages exchanged between the dongle and the battery

AA  SR:01  TR:02  LN:07  DATA:BE 0A BA C6 3A 46 BA                                                        CS:8C 03 
AA  SR:02  TR:01  LN:03  DATA:25 E0 F6                                                                    CS:01 02 
AA  SR:01  TR:02  LN:02  DATA:E7 E7                                                                       CS:D3 01 
AA  SR:02  TR:01  LN:19  DATA:BF CE B8 79 33 A3 B5 AF 29 9F B7 1B 3C 47 B9 F5 39 67 BA 2B 05 AB 85 C6 3D  CS:9C 0C 
AA  SR:01  TR:02  LN:04  DATA:1C E0 DC E7                                                                 CS:C6 02 
AA  SR:02  TR:01  LN:13  DATA:31 FC DB 3E 7E AE C2 2A 47 A6 AE 22 71 91 F3 15 77 99 FB                    CS:46 0A

Longer (60s) sample attached.

Here is how the battery looks inside (unfortunately no marking on the microporcessor). The LED that can be seen on the left side of the PCB blinks when the battery is self-discharging (this unfortunately cannot be seen when the battery is not opened).

It's a nice gadget (and I love gadgets) but the last I looked, there were only two battery packs available and that was from only one vendor who apparently is unable to ship to the US. Maybe they can ship elsewhere in the world.

Originally Posted by georgeg

Maybe they can ship elsewhere in the world.

They can. I've got one such battery.

the world does not need a proprietary battery telemetry protocol imo

-=dave

Now if they could just resume shipping to the US. Or persuade someone else to also produce compatible battery packs.

Originally Posted by pawelsky

They can. I've got one such battery.

Originally Posted by georgeg

Now if they could just resume shipping to the US. Or persuade someone else to also produce compatible battery packs.

Try Aliexpress.

Keeping this on one connector-type and having protocol fully closed cannot be a goos thing for distribution.

That said, I like the idea

Added pictures of battery internals to the first post