Lithium-ion Battery Pack v25.11 Requirements + Value Proposition
Requirements
These requirements use "shall" for mandatory/must-have requirements and "should" for recommended/nice-to-have requirements.
The battery pack shall have a nominal voltage of ~18V.
The battery pack shall have a capacity of 2500 mAh or more.
The battery pack shall be rechargeable.
The battery pack shall use a Lithium-ion chemistry.
- Should use Li-ion,LiFePO4, NMC or equivalent
- Shall NOT use LiPo(RC lipo) , since this chemistry needs more careful handling of charging/discharging, fire hazard.
The battery pack shall use widely available batteries that are easy to source.
The battery pack shall have a BMS. TODO: Need more specific safety requirements after deciding on a chemistry.
The battery pack shall have a snap-in interface suitable for cordless power tools.
The battery pack should be stackable in parallel to increase capacity.
The battery pack should be stackable in series to increase voltage.
The battery pack should have a replaceable interface. Replaceable as in support different interfaces to different things. And as in repairable I suppose.
Notes by User: Eric
- Great start!, i didn’t want to write over your work, but here are some thoughts/ideas of mine:
- ”Modular BMS Topology” such that
- Each “Pack” Has The Following:
- Per-Cell Measurements of Voltage/Amps etc
- Per-Cell Thermal Measurements
- A BMS Capable of Cell Balancing , and Per-Cell State of Charge / State of Discharge / State of Health
- It should also need to be able to show this in a simplified manner (such as the industry standard 25% Gradients 4x Light Bars and a “check” button etc, as well as via one or more Communications Protocols to enable Inter-Battery Pack Communication, Battery Pack-Charger Communication, and Battery Pack-Tool Communication
- Main use case is not letting the battery be used on tools that will overwork it, allow for charging stations or dongles to give detailed information on the BMS’s info, and to allow for your mentioned Voltage/Amp stacking for larger devices. Also could be used for on-tool battery notifications etc
- It should also need to be able to show this in a simplified manner (such as the industry standard 25% Gradients 4x Light Bars and a “check” button etc, as well as via one or more Communications Protocols to enable Inter-Battery Pack Communication, Battery Pack-Charger Communication, and Battery Pack-Tool Communication
- Each “Pack” Has The Following:
- ”Modular BMS Topology” such that