rcr123 question, is my theory right

[roopeseta]

Someone who has had similar experiences with this, it would be very nice if you could tell how it went with you thanks.

Few months back i bought my first led flashlight. Its a 2xcr123 3W luxeon k2 lamp.

Few days ago i bought 4x rcr123 600mah batteries and they seem to be protectected because i can see small "things" on the battery under the label.

I could run my lamp for 20-25minutes at full light and then it suddenly just shut down. I read that that was the over discharge protection that went on and my question now is this:

If a protected cell goes off automatically when that right voltage level is reached (that 2.5v something, my voltage meter is broken so I cant measure what it is) then its really not 100% empty?

And if its not really 100% empty (which it never should be), I dont need to keep it the 3 hours in the recharger?

In the manual it says keep this battery 3 houers in the charger and then it is full. But 3 hours is a long time. Now I wonder did the battery maker calculate that it takes 3 hours for a "protection enabled" battery to reach its full capacity or was it just calculated for an empty one (which would be a mistake on the company).


As you can see in the picture (scroll down), it says this outputs 4.7v, 370mah. (the recharger)

Why do i need to wait 3 hours instead of for example 2 hours for this to be recharged? This charger seems to have a 3 houer timer in it and after that it goes green. So it doesnt notice when its actually full and then stop recharging it.

I just want to cut down the charging time so does it really take 3 houers 370mah to recharge a 600mah battery that has not been 100% discharged (which it shouldnt be i know, but you understand what i mean.

(today im going to test this with 2x 2 houer recharged batteries and then i see if this has 20-25min running time, just like the 3 hour recharged ones. If it does, then i know my batteries really only need 2 hours of recharging)

THe shop where i bought these from say that this needs to be recharged 2 hours. (internet shop)

(btw, my country finland has SO expensive batteries, one 600mah li-ion costed 17.8 dollars at the most cheapest place i could find and in the end a recharger + 4 batteries = 94.2$. is this uniross brand even good or my flashlight, "PalmBlaze"?)

if you know anything, thank you very much :thanks::thumbsup:

 

[half-watt]

If a protected cell goes off automatically when that right voltage level is reached (that 2.5v something, my voltage meter is broken so I cant measure what it is) then its really not 100% empty?

And if its not really 100% empty (which it never should be), I dont need to keep it the 3 hours in the recharger?

In the manual it says keep this battery 3 houers in the charger and then it is full. But 3 hours is a long time. Now I wonder did the battery maker calculate that it takes 3 hours for a "protection enabled" battery to reach its full capacity or was it just calculated for an empty one (which would be a mistake on the company).


As you can see in the picture (scroll down), it says this outputs 4.7v, 370mah. (the recharger)

Why do i need to wait 3 hours instead of for example 2 hours for this to be recharged? This charger seems to have a 3 houer timer in it and after that it goes green. So it doesnt notice when its actually full and then stop recharging it.

short answer: yes, you need to leave it in the charger for the full 3h. however, if your charger is functioning based solely upon TIME, then you might be able to take it off sooner than 3h, or you might have to leave it on longer than 3h. TIME charging is generally NOT a good thing. Too many variables. If however, your charger is Voltage sensing (or uses another more sophisticated method to determine state of charge - many do nowadays, but we get into those here), than you should leave it on the charger until the charger indicates that it is "fully" charged. taking it off sooner will result in less charge than is possible for the battery, thereby reducing burntime performance.


longer answer: think about it this way. suppose you had a specially made drinking glass. Part way up from the bottom of the glass, the glass has a glass plate with a very small hole in it. Now because the hole is so small, you must fill this special glass very slowly or it will overflow without completely filling the volume beneath the glass plate with the small hole (compare this to electrons only coming out of the charger and into the battery at a slow rate - think of the overflow of water as an EXPLOSION if you charged the battery too, too fast and the protection circuit failed for some reason).

ok. filling the glass slowly allows water to get through the hole in the glass separaing plate and fill the lower volume.

now, suppose further that you filled it slow enough that the lower volume beneath the plate with the tiny hole was completely full. what would happen? of course, the water would start to fill the portion of the glass above the separating glass plate.

Further suppose that it took 3h to fill the entire glass to the brim before a pressure plate/sensor that the glass was resting on recognized that the glass was full just before overflowing and shut off the water coming out of the faucet that was being used to fill the glass.

Now, suppose you stopped the filling after just 2h. The bottom of the glass below the separating plate is full, but the volume above that plate is only partially full.

Now, you're real, real thirsty and want a drink of water from the glass. You'll tip up the glass and only get, let's say 4oz of water (instead of 6oz of water if you had let the glass fill for 3h right up to its brim).

After you drink all the water (4oz in this example) above the glass plate, very little water will trickle out of the tiny hole in the separating plate (think of the separating plate as analogous to the PROTECTION CIRCUIT - the only difference is that the Prot. Ckt. won't allow any "trons" to flow below a lower cut-off voltage).

This is pretty much what is happening with the charging on the charger and discharging during use with the protected battery. you'll get fewer electrons out of the battery if you don't charge the battery up fully. you just can't get to the electrons below the protection circuit's lower voltage cut-off level. besides, you wouldn't want to (as you yourself stated in your Post) since it could damage the battery, or worse!

I hope this little example helped. If it only confused you more, i apologize.

 

[roopeseta]

i just finished testing. I recharged only 2 houers these batteries and then put the lamp in a water filled plastic jar and put it on. (water so its not so hot).
It was on for exactly 25 minutes. It was also on 25 minutes with the 3 hour charged batteries so from now on i will mostly be charging these for 2 hours at a time. yipii