# Cell Pack Designer — 18650 21700 LiFePO4 Calc

> 18650 21700 LiFePO4 Calc (iPhone/iPad app by Yoshifumi Sato.)

- Source: https://appshunter.io/ios/app/cell-pack-designer/id6795739336 (this page in markdown: same URL + `.md`)
- Developer: [Yoshifumi Sato](https://appshunter.io/developer/6780413827)
- Category: Utilities
- Price: $4.99
- Age rating: 4+
- Requires: iOS 17.0 · 12 MB
- Languages: American English
- Released: 2026-08-06
- Data updated: 2026-08-12
- User reviews in markdown: https://appshunter.io/ios/app/cell-pack-designer/id6795739336/reviews.md

## What is Cell Pack Designer?

Cell Pack Designer helps you plan DIY battery packs built from 18650, 21700, or LiFePO4 cells, before you spend money on parts.

Pick a cell preset (or enter your own specs) and a series x parallel configuration, and instantly see:

- Pack nominal and full-charge voltage
- Total capacity in Ah and Wh
- Continuous and peak discharge current
- Estimated pack weight
- Estimated build cost (cells, BMS, nickel strip, wiring)
- Recommended BMS current rating, with a warning if your BMS is undersized
- Estimated voltage sag under load

Every default value, cell capacity, cost, weight overhead, is editable, so the numbers match the exact cells and prices you are actually using.

Save multiple pack designs and compare them side by side to find the configuration that fits your project, whether that is an e-bike, a solar storage bank, a power tool pack, or a robotics project.

Cell Pack Designer works completely offline. Nothing you enter ever leaves your device.

This app is a planning and estimation tool. Always follow proper safety practices, use a real BMS, and verify specs against your actual cell datasheets before building a physical pack. Lithium battery packs can be dangerous if built incorrectly.


## Version history (last 1 release)

### 1.0 — 2026-08-07

No release notes.

## More apps by Yoshifumi Sato

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- [Progressly – Body Progress](https://appshunter.io/ios/app/progressly-body-progress/id6789591055)
- [Holdly – Isometric Timer](https://appshunter.io/ios/app/holdly-isometric-timer/id6789790139)
- [かんじ1年生 小学1年の漢字ドリル](https://appshunter.io/ios/app/1-1/id6789917332)
- [かんじ3年生 小学3年の漢字ドリル](https://appshunter.io/ios/app/3-3/id6790055787)

All apps by Yoshifumi Sato: https://appshunter.io/developer/6780413827

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-08-12.*