Hope it helps since Bosch did not make this part available to buy for users with multiple vehicles to charge.
BHPian Vidyanand recently shared this with other enthusiasts.
DIY Quick Connector for Bosch C7 (and C3) Car Battery Charger
I needed an extra quick connector to charge my TVS Wego, which has limited use for local errands and would often get discharged by sitting idle. The battery is difficult to reach compared to a car. You need to unscrew 4 bolts to remove a panel and then pull out the battery to access the terminals to clamp. The quick connect harness for Bosch C7 would take care in avoiding this easily.
Although searching with the part did result in Amazon listing but was never available Bosch C75AC0 Quick Connect Cable Harness for C7 Battery Charger with Built-in Cable Fuse. I shot an email to Bosch customer service which was of no help. They redirected to check with local Bosch Car service center who never had this product. So eventually decided to go the DIY way as earlier suggested in the thread.
Items needed:
- XT60 connector pair – 1
- Electrical Wire Crimp Terminals Connectors 4-6 sqmm (this is same size as in the C7 charger) – 4
- 1.5 sqmm wires – needed length in pair
- Shrink Wrap
- Soldering Kit
I had all items available at home except the connectors. XT60 was ordered on amazon while the battery terminal was sourced from local electrical shop.
Task is simple, make two sets of the XT60 -to- Battery Terminal Connector. One with Male one and the other with Female XT60 connector. Pics to clarify.
One set needs to be attached to the C7 clamps.
Fix the other set to your car (or scooter ) battery terminals. I fixed in scooter and routed to the storage compartment for easy access. Shrink wrap/zip tie the cables together along the length as needed so that they do not move around. I made a small hole to let the cable in the compartment. Missed taking the battery terminal connected pic (will request mods to attach later when I access the battery in the future).
That is it. Just pop up the seat (hood in your car) and connect it to charge multiple vehicles as needed. Just add one set for each vehicle, making sure that the all vehicles must use the same connector end (Male or Female) while the C7 attached is opposite end. XT60 can be bought individually of all Male or all Female as needed.
Significant Pointers
- Can use any such easily available connector pairs, e.g. XT90 or other.
- The connector has +ve and -ve marking to make it easier. I used blue wire for negative and red for positive.
- Connector already soldered with wire are also available in case you want to skip soldering. Simple connect or crimp will ease the job.
- Battery Terminal ring that I used was perfect for the 12V battery in Wego. Do check for size if you car battery has bigger terminal bolts. I went with the ring size in C7 kit assuming this would work.
- This is not water proof at the connectors without a cap. One can choose a water proof connector set, if available.
To reduce risk, I kept the the connector with the cavity attached to C7 clamps while the one in scooter would not accumulate water. Additionally, I used a USB-A Terminal cap to mold as a cap in the scooter. 
That’s all folks, hope it helps since Bosch did not make this part available to buy for users with multiple vehicles to charge.
Check out BHPian comments for more insights and information.
