My buddy and I recently went cave exploring to the Ape Caves in Washington the other week and I really want to build a overkill headlight/flashlight combo and was toying around the idea of using 16850 batteries which are the same ones in laptop battery packsā¦ It turns out I have 32 of them I arranged in a 6x5 arrangement giving me 12volts at some unknown MAH ratingā¦ it has powered a little over 10 watt led for 8 hours with less then 1/2 volt voltage drop over that timeā¦ āwith a constant current regulatorā
Although 32 of those batteries is heavyā¦ and stupid.
I was going to buy 2 of these batteries and attach them together for 10400Mah @ 11.1 volts. āOverkill I knowā
I have 3 of these things sureelectronics.net/goods.php?id=1288 which is the photo attached. ātempted to do 3 voltage regulators and 3 leds for 30 watts totalā
The general layout is
Batteries --> Ubec --> switch --> Linear Voltage Regulator āAttached photoā --> LED
or
Batteries --> Ubec --> switch --> 3 x Linear Voltage Regulator āAttached photoā --> 3 x LED
I need to know what type of UBEC to order for my lipoās so they dont go chernobyl while Iām trying to see in the darkā¦ and what usually happens when a ubec senses that the voltage is too low, will it just cut power or will it beep at me?
Yeah I had also come to that conclusion looking at all the stuffā¦ It was more so how to work with Lipoās in general while keeping their life expectancy high.
so I have a bench PSU a extech 382260 power supply, when I power this 10-20 watt led and start increasing power the brightness is at its max at about 12-13 volts and I can dim it until it gets to 8.53 volts then its completely off with about .005 amps of current draw from the circuit, with that said if I powered this with a 11.1 volt lipo would I just run it until the power dropped to 8.53 volts then charge it?
As I had read you dont want to go below 3 volts a cell , which would be 9 volts, taking it to 8.53 would be less and potentially ruin the batteriesā¦
Reasons why I ask as I have never worked with these types of batteriesā¦
Iām tempted to invest in some Lifep04 batteries and avoid all this battery hoopla.
It depends on the quality of the batteries. Most manufactures recommend to not discharge <3v per cell UNDER LOAD. But some has a lower limit at 2,8v (3S = 8,4v). The real limit is around 2,5 volt but for safety most manufactures say 3 volt. Iāve also read that you shouldnāt discharge 100% of capacity but 75-80% to get the best performance from your LiPoās.
There is also a very big difference in what current draw you have on the battery when reaching the lower limit. At higher current draw they use a higher cut-off limit (3,3 - 3,4v).
What Iām trying to say is that your 8,53v limit might work on a 3 cell if the manufacture say 2,8v. But donāt blame me if you ruin the batteryā¦
These leds I have at 12volts draw 1.517 amps and would potentially have 3 of these with 3 current regulators so thatās about 4.5 - 4.8 ampsā¦ It also is possible I could simply run a single led and single regulator / These lipoās are weird.
