Timeline for NiMH Battery Indefinite Charging
Current License: CC BY-SA 4.0
7 events
| when toggle format | what | by | license | comment | |
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| Oct 14, 2020 at 2:19 | comment | added | squarewav | Interesting comments. I'm using 2/3AAA 400 mAh so I might still get away with this. But long term it sounds like I should move to a PIC so that I can code around problems. | |
| Oct 13, 2020 at 17:54 | comment | added | DrMoishe Pippik | @squarewav, two caveats: 1. A comment above warns some new cells do not have the recombination catalyst. 2. Even with catalyst, continuous charging at C/12 could burst cells, but is not likely to cause a large leak of alkaline electrolyte, and is not a fire hazard, at least for smaller "flashlight" size cells.. (Overcharging Li cells, on the other hand, is far more dangerous.) | |
| Oct 13, 2020 at 17:47 | comment | added | DrMoishe Pippik | @SamGibson, thanks for the caveat! Though I haven't done research, my experience is with "AA" (HR6) ~2,000 mAh cells only, and all brands I've used, including low self-discharge Eneloop, withstand 1/100 C for years with no noticeable degradation. Of course, that does not apply to other cells. | |
| Oct 13, 2020 at 14:45 | comment | added | SamGibson♦ | Hi DrMoishe, regarding: "Most NiMH now contain a catalyst to reunite the gases" User Russell McMahon has done lots of research. In various answers e.g. here, here, here & here he discusses NiMH batteries & reports that modern NiMH (especially larger-capacity) cells are more likely not to have the catalyst that would allow long-term trickle charging, and would be damaged by that. Any thoughts? | |
| Oct 13, 2020 at 5:36 | comment | added | squarewav | Thanks @DrMoishe. So I suppose my method is worth a try then. In my scenario voltage limiting is current limiting since the 14.2V limit of the current source is below the nominal voltage of the pack. A shorted cell would be a problem. But the whole pack would just be discarded anyway. So as long as there's no danger of something bursting open and making a mess (which seems unlikely at C/11.8) I think I can overlook that for now. | |
| Oct 13, 2020 at 5:29 | vote | accept | squarewav | ||
| Oct 13, 2020 at 4:08 | history | answered | DrMoishe Pippik | CC BY-SA 4.0 |