Max. Charging Capacity for Powerex MH-C401FS
- Thread starter jusko
- Start date
Help Support Candle Power Flashlight Forum
coppertrail
Enlightened
- Joined
- May 21, 2006
- Messages
- 920
I would stay away from using Fast Mode on this charger as it tends to overheat cells.
Its hard to say the max capacity of cells that it can charge. I've charged 2700 mAh cells using slow mode, and slots 2 & 3 took much longer to finish (which makes me wonder if it was in fact missing termination). 350 mA is a bit low for higher capacity cells. I'm going to use it solely for Eneloop, Hybrid, and lower capacity NiMH cells from now on.
Its hard to say the max capacity of cells that it can charge. I've charged 2700 mAh cells using slow mode, and slots 2 & 3 took much longer to finish (which makes me wonder if it was in fact missing termination). 350 mA is a bit low for higher capacity cells. I'm going to use it solely for Eneloop, Hybrid, and lower capacity NiMH cells from now on.
coppertrail
Enlightened
- Joined
- May 21, 2006
- Messages
- 920
I used it to charge my 2700 mAh cells about 12 times, and I didn't notice a reduction in capacity. I don't know that 12 charges is enough to say that cells don't need to be conditioned while using this charger. Maybe some other folks who've used this charger more extensively can comment on their experiences.
To add to this, let's take a look at the recommended charging rates. Many other threads, and the MH-C9000 manual, recommend charging at a rate between .5 - 1C (C = total capacity of cell in mAh). If you charge 2700 mAh cells in the 401FS using the slow charging mode, you're charging at .1 C, much lower than the recommended .5 - 1C range. At lower charge rates, you risk a missed charge termination, which can lead to overcharging and cell damage. This is why I will no longer use the 401FS for higher capacity cells. I'm not saying that the 401FS will miss termination, or that it will damage cells, but simply that the potential is there given the 350 mAh charge rate.
I've read a couple reviews where cells simply get "too hot" when using fast mode. Since excessive heat is know reduce the overall lifespan of the cell, I simply won't use the fast mode on this charger.
To add to this, let's take a look at the recommended charging rates. Many other threads, and the MH-C9000 manual, recommend charging at a rate between .5 - 1C (C = total capacity of cell in mAh). If you charge 2700 mAh cells in the 401FS using the slow charging mode, you're charging at .1 C, much lower than the recommended .5 - 1C range. At lower charge rates, you risk a missed charge termination, which can lead to overcharging and cell damage. This is why I will no longer use the 401FS for higher capacity cells. I'm not saying that the 401FS will miss termination, or that it will damage cells, but simply that the potential is there given the 350 mAh charge rate.
I've read a couple reviews where cells simply get "too hot" when using fast mode. Since excessive heat is know reduce the overall lifespan of the cell, I simply won't use the fast mode on this charger.
Last edited:
coppertrail
Enlightened
- Joined
- May 21, 2006
- Messages
- 920
My bad, for some reason I have it in my head that the slow mode on the 401FS is 350 mA 
That said, you'd still be charging @ .1C, much less than the .5 - 1C range.
That said, you'd still be charging @ .1C, much less than the .5 - 1C range.
coppertrail
Enlightened
- Joined
- May 21, 2006
- Messages
- 920
Hi Verge -
You're not off topic with this question It's equal to the rated mAh of the battery.
For example, say you want to charge a 2700 mAh cell at .5C. You'd divide 2700 by .5, which equals 1350. To charge your cell at .5C, you'd set your charger to a charge rate of 1350 mA (or close to this value).
You're not off topic with this question
It's equal to the rated mAh of the battery.For example, say you want to charge a 2700 mAh cell at .5C. You'd divide 2700 by .5, which equals 1350. To charge your cell at .5C, you'd set your charger to a charge rate of 1350 mA (or close to this value).
Jerry_S
Newly Enlightened
Hi Jusko. Your questions would probably best be answered by Maha. Try going to mahaenergy.com. select support and use their on-line form to ask your questions.
Hope I helped.
Jerry
Hope I helped.
Jerry
coppertrail
Enlightened
- Joined
- May 21, 2006
- Messages
- 920
If they do tell you you can safely charge 2700 mAh cells on slow mode, they're giving out conflicting information. In their MH-C9000 manual, they indicate that charging at rates lower than .5C can lead to missed charge terminations, hence overcharging.
I see on their site they sell a 401FS/2700 mAh cell combo. If their reasoning behind this combo offering is that you can charge 2700 mAh cells with the 401FS, but only on fast charge mode, you risk overheating the cells, which they most likely won't tell you.
I see on their site they sell a 401FS/2700 mAh cell combo. If their reasoning behind this combo offering is that you can charge 2700 mAh cells with the 401FS, but only on fast charge mode, you risk overheating the cells, which they most likely won't tell you.
Thanks Chris. I want to buy the 401FS is because it has been selling for about 7 years and no major negative report on it except a bit overheating. And I think MAHA has great confidence in this charger as far as durability and reliability are concerned because they offer lifetime warranty for this charger.
Best Regards
jusko
Best Regards
jusko
