# Cell Saviors

> Free online tools and educational resources for DIY lithium battery builders and solar system planners.

Cell Saviors provides a suite of free battery building calculators, planners, and guides. The site serves DIY enthusiasts building custom lithium battery packs, powerwalls, car audio battery systems, and solar energy storage.

## Tools

- [Battery Pack Planner](https://cellsaviors.com/pack-planner): Calculate voltage, capacity, runtime, and BMS requirements for a custom 18650 battery pack.
- [Battery Pack Builder](https://cellsaviors.com/pack-builder): Balance and sort cells by capacity and internal resistance into even series groups.
- [3D Battery Pack Designer](https://cellsaviors.com/battery-pack-designer): Lay out a custom pack shape and preview cell fit in 3D.
- [Powerwall Planner](https://cellsaviors.com/powerwall-planner): Size a DIY powerwall system with battery storage, inverter, and solar recommendations based on ZIP code.
- [BMS Picker](https://cellsaviors.com/bms-picker): Find the right battery management system by series count, current demand, and cell chemistry.
- [Car Audio Calculator](https://cellsaviors.com/car-audio-calculator): Size a lithium battery bank for car audio with cell presets and alternator compatibility checks.
- [Battery Pack STL Generator](https://cellsaviors.com/battery-pack-stl-generator): Generate 3D-printable STL files for cell holders, enclosures, lids, and gaskets.
- [Pack Validator](https://cellsaviors.com/pack-validator): Validate a battery pack design for overcurrent, BMS mismatch, wire gauge, and thermal risks before building.
- [18650 Internal Resistance Calculator](https://cellsaviors.com/cell-resistance): Estimate cell internal resistance, current capability, and heat from loaded and unloaded voltage measurements.
- [Wire Resistance & Voltage Drop Calculator](https://cellsaviors.com/wire-resistance): Calculate wire resistance and voltage drop for common conductor materials and gauges.
- [Battery Runtime Calculator](https://cellsaviors.com/runtime-simulator): Estimate battery runtime under real-world load, duty cycle, chemistry, and temperature.
- [Battery Cost & Performance Calculator](https://cellsaviors.com/cost-optimizer): Compare cell options by cost, weight, cycle life, and safety margin for a target voltage and capacity.
- [Battery Pack Thermal Visualizer](https://cellsaviors.com/thermal-visualizer): Visualize thermal hotspots in a battery layout before committing to a pack design.
- [Battery Pack Safety Checklist](https://cellsaviors.com/safety-checklist): Generate a personalized safety checklist based on pack specs, enclosure, environment, and transport needs.
- [BMS Recommender](https://cellsaviors.com/bms-matcher): Get BMS product recommendations matched to pack series count, current demand, and chemistry.

## Articles

- [Blog](https://cellsaviors.com/blog): Guides and articles on DIY battery building, powerwalls, and lithium battery technology.
- [Battery Storage](https://cellsaviors.com/battery-storage): Articles about battery storage systems and cell technology.
- [Powerwalls](https://cellsaviors.com/powerwalls): Guides on building DIY powerwall and solar storage systems.
- [Personal Electric Vehicles](https://cellsaviors.com/personal-electric-vehicles): Articles about e-bike, scooter, and EV battery builds.

## Resources

- [Essential Tools & Supplies](https://cellsaviors.com/essential-tools): Curated list of tools and supplies for DIY battery building projects.
- [About](https://cellsaviors.com/about): About Cell Saviors and its founders.