Post Reply 
HP97 battery pack rebuild
02-11-2016, 11:02 AM (This post was last modified: 02-11-2016 11:03 AM by Hans Brueggemann.)
Post: #7
RE: HP97 battery pack rebuild
(02-11-2016 12:12 AM)rprosperi Wrote:  I agree with Den, it will work, but with these relatively large NiMH cells, it would probably take 3-4 DAYS to fully charge (assuming using the normal HP-97 charger.

The DC charge current into the battery pack is approx. Ich = 170 mA (measured on my HP-97) when using the standard HP-97 charger. for minimum overcharge of the battery pack with a given amp-hours of a single cell, you calculate the charging time as

Tch = 1.1 * Qcell / Ich (assuming a fully discharged pack!)

example: for the battery pack containing cells with 2400 mAh each, your time to fully charge the pack is
Tch = 1.1 * 2400 mAh / 170mA = 14.12 hours
(using HMS on your trusty HP-41C gives 14 hours, 7 minutes, 4 seconds)
Find all posts by this user
Quote this message in a reply
Post Reply 


Messages In This Thread
HP97 battery pack rebuild - Jlouis - 02-10-2016, 06:47 PM
RE: HP97 battery pack rebuild - d b - 02-10-2016, 07:33 PM
RE: HP97 battery pack rebuild - Jlouis - 02-10-2016, 07:41 PM
RE: HP97 battery pack rebuild - d b - 02-10-2016, 09:26 PM
RE: HP97 battery pack rebuild - rprosperi - 02-11-2016, 12:12 AM
RE: HP97 battery pack rebuild - Hans Brueggemann - 02-11-2016 11:02 AM
RE: HP97 battery pack rebuild - Dieter - 02-11-2016, 11:23 AM
RE: HP97 battery pack rebuild - Dieter - 02-11-2016, 01:47 PM
RE: HP97 battery pack rebuild - TASP - 02-11-2016, 12:42 AM
RE: HP97 battery pack rebuild - rprosperi - 02-11-2016, 03:08 PM
RE: HP97 battery pack rebuild - Jlouis - 02-11-2016, 03:42 PM
RE: HP97 battery pack rebuild - Dieter - 02-11-2016, 11:15 PM
RE: HP97 battery pack rebuild - rprosperi - 02-11-2016, 11:23 PM
RE: HP97 battery pack rebuild - Jlouis - 02-12-2016, 12:55 AM
RE: HP97 battery pack rebuild - d b - 02-12-2016, 04:01 AM
RE: HP97 battery pack rebuild - Jlouis - 02-16-2016, 04:11 PM
RE: HP97 battery pack rebuild - Dieter - 02-16-2016, 07:28 PM
RE: HP97 battery pack rebuild - Jlouis - 02-16-2016, 07:42 PM
RE: HP97 battery pack rebuild - Jlouis - 02-18-2016, 01:49 PM
RE: HP97 battery pack rebuild - quantalume - 02-18-2016, 07:18 PM
RE: HP97 battery pack rebuild - d b - 02-19-2016, 07:04 AM
RE: HP97 battery pack rebuild - Dieter - 02-19-2016, 07:11 PM



User(s) browsing this thread: 1 Guest(s)