Application question: Titanium 12000mAh D cell

[rhymemaze]

Hi,

I have these electronic trash cans from Costco that take 4 D batteries. You wave your hand over the sensor and the trash lid opens. Right now I have 4 Duracell alkaline in there that have been going strong for almost 2 months now.
My question is how do you think these Titanium D cells will perform in comparison to the alkaline? Would the Titanium last as long as the alkaline? I ask because the Titanium are not LSD cells....the last thing I want to do is charge the D cells once a week though not sure if discharge would be that quick or not on the Titaniums compared to alkaline.

Also, how do the Titanium D cells compare to the Tenergy D cells in quality? Should I consider those over the Titaniums or just forget them both and look for the LSD D cells for this application?

Thanks.

 

[gswitter]

I doubt they'll last as long as the Alkalines, but that's not really the point. How often are you willing to recharge them? I had a set of Titanium Ds sitting in a box for well over a year, and they were still usable. I didn't test their capacity, but they all measured over 1.2V, and three of them had no trouble firing up a light that pulled ~2.5A.

 

[TakeTheActive]

Match the Cell to the Application...

...Right now I have 4 Duracell alkaline in there that have been going strong for almost 2 months now.

My question is how do you think these Titanium D cells will perform in comparison to the alkaline? Would the Titanium last as long as the alkaline? I ask because the Titanium are not LSD cells....the last thing I want to do is charge the D cells once a week though not sure if discharge would be that quick or not on the Titaniums compared to alkaline...

I've been using rechargeable batteries for ~20 years, but I learned more about them in the past few months reading the archives here than I ever knew before.

I bought six Vinic 6000mAh Ds back in 2002 (along with four Tysonic 4500mAh Cs) and with what I now know, it was a waste of money. They spend the bulk of their life in 'self-discharge' mode, building up internal resistance, WAITING to be used now-and-then.

For ANY application, I would determine the current draw and daily usage and then pick a capacity that would require a recharge somewhere between a week and a month max. Look at the potential available cycles. If you got 500 cycles out of a set of cells, that could be weekly charging for 10 years. Monthly would go out to 41 years, which you would never reach since the cells would just grow old and die. Maybe a C cell (or even an AA!) in an adapter would work out better for you.

Also, what kind of 'safety' mechanism is in place to prevent you from discharging the NiMHs too deeply? Maybe a NiCD cell, which can handle abuse better, would be more appropriate.

IMO, matching the cell to the application is going to be more cost-efficient than just throwing the largest capacity NiMH cell at it.

 

[rhymemaze]

Re: Match the Cell to the Application...

I doubt they'll last as long as the Alkalines, but that's not really the point. How often are you willing to recharge them? I had a set of Titanium Ds sitting in a box for well over a year, and they were still usable. I didn't test their capacity, but they all measured over 1.2V, and three of them had no trouble firing up a light that pulled ~2.5A.

I guess I'd like to charge them like every month or 2. I don't want to have to charge the batteries every week.

...
For ANY application, I would determine the current draw and daily usage and then pick a capacity that would require a recharge somewhere between a week and a month max. Look at the potential available cycles. If you got 500 cycles out of a set of cells, that could be weekly charging for 10 years. Monthly would go out to 41 years, which you would never reach since the cells would just grow old and die. Maybe a C cell (or even an AA!) in an adapter would work out better for you.

Also, what kind of 'safety' mechanism is in place to prevent you from discharging the NiMHs too deeply? Maybe a NiCD cell, which can handle abuse better, would be more appropriate.

IMO, matching the cell to the application is going to be more cost-efficient than just throwing the largest capacity NiMH cell at it.

These are the guys I am using right now (no detailed specs though):
http://www.ninestarsusa.com/retail/General/stainless-dzt-50-9.aspx
http://www.ninestarsusa.com/retail/General/stainless-dzt-8-1a.aspx


I didn't look until now :huh: but from the FAQ's it says:
4. How does the Motion Sensor Trash Can operate?
The Motion Sensor Trash Cans are battery operated. Each trash will get a minimum of 10,000 open and closings before new batteries are required. In most households that amount of openings and closings means the batteries should last a minimum of six months and could last up to a year.


Now it makes me wonder if I need the D NiMH cells for this application at all? 12-D Duracell alkaline cost me ~$13 last time.

I figure the 13 gallon can gets opened ~50 times a day on average so in theory the alkaline batteries should last ~6 months according to their 10,000 "open/close" specs. The smaller bathroom can gets opened maybe 10 times a day so that one should last forever! I kid but I am guessing I won't have to change that for at least a year.

 

[Mr Happy]

So what are you keeping in your trash cans anyway? Gold?

Battery powered trash cans seems like a really expensive way to look after your rubbish. I have a trash can that opens automatically when I wave my hand over it, and it needs no batteries at all (it has a spring).

 

[rhymemaze]

So what are you keeping in your trash cans anyway? Gold?

Battery powered trash cans seems like a really expensive way to look after your rubbish. I have a trash can that opens automatically when I wave my hand over it, and it needs no batteries at all (it has a spring).

I am into gadgets.
It is odd that the trash cans BOTH take 4 D batteries but they are a cool addition to our house.

I need to get a new charger (I have an older Sanyo NC-MQNO5U in use right now). This application was one reason I was looking into a charger that would accept D cells. Now I am thinking that I may try the adapter route as TakeTheActive suggested, or just buy the alkalines again when the time comes. I need to refocus my reading here for a solid AA/AAA charger and think it through a bit.

 

[TakeTheActive]

Re: Match the Cell to the Application...

I guess I'd like to charge them like every month or 2. I don't want to have to charge the batteries every week...

...Now it makes me wonder if I need the D NiMH cells for this application at all? 12-D Duracell alkaline cost me ~$13 last time...

Sounds like another application for LSD AAs w/adapters (Costco Eneloop package?) and a good 'Charger/Analyzer' like the BC-900 or MH-C9000.