Delta Peak setting for NiMh batteries

[Alan_Perse]

Does anyone know what's the best Delta Peak setting for charging NiMh batteries. It says in the manual for my new cockpit SX that the delta peak should be set to 5mV/cell. I tried that setting to charge my other NiMh batteries and they don't seem to be getting fully charged. At least I don't think so, I will have to investigate it more. The default setting on the charger was 15mV/ cell. That setting seemed to be fine for some of my batteries, but it over charged my cockpit SX. What does everyone else think?

[Fred]

Hi Alan,

I charge my nimh as nicd. Problem solved!
And doing so for years.
Delta can be a pain, and never managed to get a pack fully charged in nimh mode, whatever charger i used!

[Happy Days]

Years ago I could have quoted the details off the top of my head Alan, but now when I try to remember it all becomes a bit fuzzy.

The Dleta peak is (as I remember) relative to the capacity of the cell,  which is probably why you’re getting different results for different size cells. The matter is slightly further complicated by the fact that effective cell capacity changes with age (use) of the cell.

In the past when I used to use Nicads or metal-hydrides a lot ( in a different hobby) the difference in actual current stored didn’t amount to very much. (maybe a hundred mA ) And because I never used to use all the capacity of the cells before re-charging, (except when deep cycling them) the fact that a particular cell was not charged to it’s ultimate max didn’t seem to matter.

I used to set the D. peak to 15mV and charge everything at that. The purists will no doubt say that was wrong but I never had any bad experiences from doing so.

Keith.

[Alan_Perse]

Thanks for the reply lads. The reason I asked was because my Cockpit SX has a 1800 mAh battery. When I charged it at the default 15mV/cell delta peak the charger put almost 3000mAh into, at least that is what it said on the display. And as I already said the manual says the delta peak should be 5mV/cell, which seemed a bit small. I looked on the internet I read that a rate of between 3 to 8mV/cell is used by other people. What does everyone else use?