Hello!
I'm experienced engineer, who took part in many embedded devices projects. I've designed electronics (circuit, schematic, BOM, prototype) and software.
I would like to use my experience to help you with this project.
As I understood you want online (float charge and/or under-load) battery resistance tester.
Please share details about what should be done detailed.
I can program the device on my own, but I need to fit your specific requirements. I understand the scope but need your requirements list.
I'm available online since 8AM your local time. Chat with me, please!
Looking forward to hear from you soon
Best regards,
Vitaliy