HP Classic Calculator LiPo Battery Pack
Modern LiPo Battery Pack for HP 'Classic' Calculators
This is my attempt at a LiPo-based battery pack for "Classic" HP Calculators, specifically HP-35, HP-45, and HP-55. The original NiCd packs are all dead by now, and rebuilding them is difficult - assuming you can even find a pack to rebuild. I thought it would be fun to use a rechargeable LiPo battery, and include the circuitry to re-charge via USB as well.
LiPo chemistry has very specific care-and-feeding when it comes to recharging, You cannot use the HP AC charger to recharge this pack! Don't even try it. Not kidding.
The basic idea is to use a gold-flashed (ENIG) PCB as the contact substrate, and mount the LiPo, USB micro B receptacle, and charging circuitry on the opposite side. A pair of laser-cut 'endcaps' locate the assembly within the battery well. and allow the compartment cover to hold it in place.
More information and downloadable files are available on the Hackaday project page and at GitHub
HP Classic Calculator LiPo Battery Pack
*PCBWay community is a shared platform and we are not responsible for any design issues.
- Comments(1)
- Likes(0)
- 0 USER VOTES
- YOUR VOTE 0.00 0.00
- 1
- 2
- 3
- 4
- 5
- 6
- 7
- 8
- 9
- 10
- 1
- 2
- 3
- 4
- 5
- 6
- 7
- 8
- 9
- 10
- 1
- 2
- 3
- 4
- 5
- 6
- 7
- 8
- 9
- 10
- 1
- 2
- 3
- 4
- 5
- 6
- 7
- 8
- 9
- 10
More by Tom LeMense
-
-
Open Source Very Large Stick - Freejoy & MMjoy2 breakout board
520 0 0 -
RF Control training board for students based on ESP32 C3
701 0 2 -
Aquarius+ Computer, Standard PCB
929 0 5 -
KINETIC COASTERS with a TWIST! Laser or 3D Print some DIY Magic
617 0 1 -
RPI - 8 IO PLC With ATTiny85 Watch Dog
540 0 1 -
Nintendo Famicom HVC-001 Controller Shells
638 0 1 -
COMMODORE 128 DIAGNOSTIC REV.785260 KEYBOARD DONGLE
600 0 4 -
COMMODORE 128 15KHz DISPLAY ADAPTER (C128 80 COLUMN ADAPTER)
817 1 7