AA rechargeable batteries - Page 1
Forum section: electronics / general

author: sony mavica
author_rank: Frequent Contributor
timestamp: January 18, 2016, 08:27:11 am
content: my mate just gave me his old cameras the other day in like new condition he hardly ever used its a 10mp he has now upgraded to a dslr he hates cameras that take AA batteries he gave me a charger and a brand new pack of AA 2x 1.5v rechargeable batteries this is the charger he gave mehttp://www.dollargeneral.com/product/index.jsp?productId=12579329so i put them in the charger and came back about 5hrs latter took them out they where warm and also have leakedso i tried my 1.2v rechargeable batteries i bought about a week ago for my wii controller in the charger came back like 6hrs latter then took them out put them in the camera and camera worked for like 1min then diedthe camera is canon a490 and i did a google and it can work with NiMH rechargeable battery do so after 6hrs of charging they should have enough charge in them right

author: mariush
author_rank: Super Contributor
timestamp: January 18, 2016, 09:00:13 am
content: That type of charger uses a low current to charge batteries, which means it takes about 8-10 hours at minimum to fill up a couple of 2500+ mAh batteries. Ideally, you leave them charging over night (14h+). 6 hours is not enough to charge good batteries.In addition, older Canon camera models have the low voltage threshold too low, they tend to say low battery and turn themselves off too soon, at around 1.28-1.3v per battery. Rechargeable batteries are around 1.35v when new and around 1.2-1.25v when completely discharged - basically, the Canon camera will ask you for new batteries even if there's 20-40% of energy still there, in the rechargeable batteries.The camera also pulls a lot of current (1-2A) for a few seconds when it charges the flash, and that sudden draw can pull the voltage on the batteries down for a few seconds and then batteries recover, but that's enough for the camera to think the batteries are discharged. The lcd display on my A580 alone uses a constant 150-200mA and when focusing or preparing to take a picture (snap picture button half-pressed) the current draw goes up to 3-400mA - i tested it by connecting the digital camera to a linear power supply.If you don't believe me, try with regular AA alkaline batteries.. with 1.65v when new, the camera will take quite a lot more pictures before saying the batteries are dead.

author: amyk
author_rank: Super Contributor
timestamp: January 18, 2016, 09:18:24 am
content: Quote from: sony mavica on January 18, 2016, 08:27:11 amSounds like you need... the Batteriser!

author: StuUK
author_rank: Frequent Contributor
timestamp: January 18, 2016, 01:04:13 pm
content: Quote from: amyk on January 18, 2016, 09:18:24 amCareful you'll invoke the batteriser troll!!!!

author: rrinker
author_rank: Super Contributor
timestamp: January 18, 2016, 01:10:09 pm
content: Only AA rechargeables I use any more are the Sanyo Enloop. After the first pack of them I picked up with a charger, I knew I would never go back. I don't use my camera very often, but it's amazing to pull it out of the drawer after 6 months and it still has a charge. I went through I don't know how many E-brand batteries, it seemed like each set had a different mAH rating and had a different charger, plus they had a very high self discharge rate. I finally broke down after hearing about the Enloops and purchased some - never gone back.

author: rollatorwieltje
author_rank: Unknown
timestamp: January 18, 2016, 02:14:03 pm
content: Quote from: mariush on January 18, 2016, 09:00:13 amI keep hearing this urban myth, but what models actually suffer from that issue? I have used an A10, A60, A75 and SX110, all used AA cells and worked fine on NiMH cells. They even recommend them in the manual if you use the camera in cold conditions or for a long time. They only advice not using NiCD, which makes sense.

author: mariush
author_rank: Super Contributor
timestamp: January 18, 2016, 03:00:52 pm
content: QuoteIt's not urban myth, it's personal experience... my own Canon A580 and my own measurements : used a linear adjustable power supply to power the camera from the external dc power jack and a 0.1 ohm current shunt to measure the power consumption ... by adjusting the voltage while camera idled (just lcd screen running), the camera showed low voltage at around 2.6-2.8v and it turned off at around 2.4v - I can't say exact numbers because it was a long time ago and because there was some voltage drop on the 0.1 ohm resistor itself.I've used rechargeable batteries to shoot hundreds of pictures and it worked fine, but the batteries are not fully discharged before camera complaints but it was obvious they still had plenty of charge.You can use rechargeable and regular batteries, they recommend rechargeable because they have more charge compared to regular batteries (2500-2800mAh vs 1000-1500mAh) but as I said, some models are quite sensitive to voltage.With such cameras, AA Lithium batteries work very well as they're about 1.6-1.8v when fully charged and can handle higher idle currents better, see for example datasheet :http://data.energizer.com/PDFs/l91.pdf

author: SteveyG
author_rank: Unknown
timestamp: January 18, 2016, 03:15:42 pm
content: So far FDK AA batteries have been the best I've used. Slow charging tends to be the best for longevity of the cell.

author: CatalinaWOW
author_rank: Super Contributor
timestamp: January 18, 2016, 03:25:52 pm
content: You don't mention the make and model number of the camera you were given. It can make a huge difference. One camera I bought would get only 8-10 pictures on a new set of alkaline batteries. Others will give hundreds of pictures on a set of batteries. Not surprisingly the makers of cameras with very short battery lifes don't advertise this characteristic in the owners manual.Also, it is worth checking the set up screen of the your camera. Some have a menu selection for the type of battery, which is used to set the low battery threshold. If the camera is set for alkaline batteries it will give very poor life when used with NiMh batteries.

author: rollatorwieltje
author_rank: Unknown
timestamp: January 18, 2016, 04:17:28 pm
content: Quote from: mariush on January 18, 2016, 03:00:52 pmThere's likely at least a diode drop in there, as the external power port doesn't charge the batteries. The current draw is also quite high, if I remember correctly it peaks at almost 2A. You pretty much lose maybe 0.3-0.4V with your shunt and using the power jack.The camera definitely doesn't fully drain the batteries, I agree with that, but I believe the reason behind that is the high current draw requirement. The batteries are considered "empty" when they can't deliver the required high current, not when they actually don't contain energy anymore.I'll see if I can charge the batteries using my R/C charger. See how much it really uses. I bet it's 80% or more (SX110 with Eneloop).

author: mariush
author_rank: Super Contributor
timestamp: January 18, 2016, 04:46:07 pm
content: You have a point about the diode drop, there's probably a Schottky diode dropping around 0.1-0.15vBut as for everything else... the camera has a sticker on the bottom saying DC in : 3.15v, and i've used 3.3v from the linear power supply and the measurements were done on the current shunt (for the current) and after the current shunt for the voltage. The camera consistently turned off at around 2.5-2.6v after the current shunt.It was a long time ago (months) and the camera uses lots of current in various modes.. from memory, i think it was something like (150-200mA with lcd on, 350-400mA when focusing or preparing to snap shots or movies, 800mA - over 1A when charging flash and taking picture and 50mA or so spikes when writing to card.

author: edavid
author_rank: Super Contributor
timestamp: January 18, 2016, 04:52:04 pm
content: Quote from: mariush on January 18, 2016, 03:00:52 pmI had the same problem with a Canon A570IS. The threshold drifted up with time, to the point where freshly charged NiMH cells would immediately give the warning. This would actually be a good application for Batterisers, except I don't think they would fit in the camera.(P.S. Does anyone know if there's an adjustment pot inside?)

author: G7PSK
author_rank: Super Contributor
timestamp: January 18, 2016, 05:15:37 pm
content: A camera my wife has ( a Fuji finepix) has the same problem OK when new but the low voltage threshold seems to have gone up and now even after putting in a new set of alkaline batteries it will give a battery exhausted warning after a few seconds of turning on, I suspect that a fet. is not being turned on fully for some reason.

author: rollatorwieltje
author_rank: Unknown
timestamp: January 18, 2016, 10:45:28 pm
content: My SX110 has the CHDK firmware on it, so I can see the actual battery voltage (top center in the image). The attached image was after about a dozen shots with flash at highest power, with 2 Eneloops discharged to 2.1V @ 0.5A. Initially the voltage recovered to about 2.25V, after about a dozen shots it was 2.145. Took some other nearly dead batteries, it refuses to work when the voltage dropped below about 2.11 for a few seconds. I couldn't take a picture with these batteries, the voltage plummeted like a brick.There's no option to set the battery type, so I'm not surprised that the low battery indicator shows up early. Pretty sure alkalines would be near useless at these voltages, considering their internal resistance rises rapidly at low charge levels.

author: sony mavica
author_rank: Frequent Contributor
timestamp: January 18, 2016, 11:54:07 pm
content: my mate sent me thisu think that would help in any way

author: edavid
author_rank: Super Contributor
timestamp: January 19, 2016, 01:36:08 am
content: Quote from: sony mavica on January 18, 2016, 11:54:07 pm(Cleaning/adjusting the battery contacts.)That helps when the problem is that the camera shuts down when you try to take a photo, but not when it detects low battery just sitting there idle.

author: profany
author_rank: Contributor
timestamp: March 06, 2016, 07:39:06 pm
content: AA baterries never gave problems, but are a litle expensive