Feathered Friends 300x250
Superior Down Sleeping Bags & Clothing

Ultralight Adventure Equipment (ULA)    

   
 
 
Lite Gear Talk

BCG Holiday Sale

Amazon.com
Backpacking Forums
BackcountryGear.com
backcountry gear

---- Our Gear Store ----
The Lightweight Gear Store
 
 WINTER CAMPING 

Shelters
Bivy Bags
Sleeping Bags
Sleeping Pads
Snow Sports
Winter Kitchen

 SNOWSPORTS 

Snowshoes
Avalanche Gear
Skins
Hats, Gloves, & Gaiters
Accessories

 ULTRA-LIGHT 

Ultralight Backpacks
Ultralight Bivy Sacks
Ultralight Shelters
Ultralight Tarps
Ultralight Tents
Ultralight Raingear
Ultralight Stoves & Cookware
Ultralight Down Sleeping Bags
Ultralight Synthetic Sleep Bags
Ultralight Apparel


the Titanium Page
WM Extremelite Sleeping Bags

 CAMPING & HIKING 

Backpacks
Tents
Sleeping Bags
Hydration
Kitchen
Accessories

 CLIMBING 

Ropes & Cordage
Protection & Hardware
Carabiners & Quickdraws
Climbing Packs & Bags
Big Wall
Rescue & Industrial

 MEN'S APPAREL 

Jackets
Shirts
Baselayer
Headwear
Gloves
Accessories

 WOMEN'S APPAREL 

Jackets
Shirts
Baselayer
Headwear
Gloves
Accessories

 FOOTWEAR 

Men's Footwear
Women's Footwear

 CLEARANCE 

Backpacks
Mens Apparel
Womens Apparel
Climbing
Footwear
Accessories

 BRANDS 

Black Diamond
Granite Gear
La Sportiva
Osprey
Smartwool

 WAYS TO SHOP 

Sale
Clearance
Top Brands
All Brands

 Backpacking Equipment 

Shelters
BackPacks
Sleeping Bags
Water Treatment
Kitchen
Hydration
Climbing


 Backcountry Gear Clearance


Stay Healthy--Eat Well

MARY JANES FARM ORGANIC MEALS

Mary Janes Farm Organic Backcountry Meals

NATURAL HIGH GOURMET MEALS

Natural High

 

Page 1 of 2 1 2 >
Topic Options
Rate This Topic
#90876 - 02/20/08 08:46 PM Solar chargers & backpacking
300winmag Offline
member

Registered: 02/28/06
Posts: 1342
Loc: Nevada, USA
As we become more dependent on batteries for backpacking (GPS units, UV water purifiers, PLRB beacons & avy beacons, digital watches, efficient LED headlamps and, yes, even our small I-pods) it seems some company needs to look more closely at a flexible, roll-up solar charger - say about 6" X 10" - with adapters to charge various sizes of batteries. Corner grommets attatching it to a backpack lid would seem an ideal location, with the batteries tucked inside the lid.

I know some of these are sold for marine use but no battery size adapters come with them...or am I greatly misinformed?

Now obviously this is extra weight that would usually be carrried only on a very long. unsupported effort. Otherwise spare batteries would be a much lighter solution.

But that's present technology. There has been a development that can take very efficient (& expensive) galium arsenide solar cells and imbed them with tiny infra red absorbing particles, upping the efficiency by a claimed 25% since present solar cells use only visible light. This is still in the prototype stage but closing in on production within a few years.

I realize few of us "need" this gadget (until it comes on the market, that is!). But let's say we take an existing unit from someone like West Marine or a sea kayak company and try to adapt it to AA, AAA coin batteries of various numbers, and the CR123 batteries in SteriPens, etc., etc. HOW IS THAT DONE??
Obviously different retainers are required for diffrent batteries shapes and sizes but the trickier part is different amperages for different batteries. No?

Eric
_________________________
"There are no comfortable backpacks. Some are just less uncomfortable than others."

Top
#90877 - 02/20/08 11:30 PM Re: Solar chargers & backpacking [Re: 300winmag]
OregonMouse Offline
member

Registered: 02/03/06
Posts: 6400
Loc: Gateway to Columbia Gorge
I'd like to see this, too. Last summer on several occasions I ran through a set of batteries a day for my digital camera. For the 7 and 8-day outings I'm planning this coming summer, that's a lot of batteries! I'm not so worried about my headlamp (my only other battery-powered gizmo at the moment) because it seems to run forever on a set--one spare set is more than enough. But if I could recharge the AA's for the camera, it would save me some weight for longer trips.
_________________________
May your trails be crooked, winding, lonesome, dangerous, leading to the most amazing view--E. Abbey

Top
#90878 - 02/20/08 11:49 PM Re: Solar chargers & backpacking [Re: 300winmag]
Trailrunner Offline
member

Registered: 01/05/02
Posts: 1835
Loc: Los Angeles
Last summer I spent 5 of the longest days of the year on the Tahoe Rim Trail. My plan was to charge my GPS (2xAAA) and my 30 gig video Ipod from the sun. To accomplish this I had a Solio charger and another homebrew charger I constructed from a couple of thin film solar panels, a 2xAAA series battery holder, a blocking diode, a little wire and of course some duct tape <img src="/forums/images/graemlins/grin.gif" alt="" />. It was similar to this. In direct sun it was pumping 100 milliamps @ about 3 volts into the cells and in theory could fully charge two 1.2 volt 900 milliamp/hour AAA cells in less than 9 hours. It sounded pretty on paper.

The panel I made was approx. 12"x4". In theory it would produce about as much power as my GPS consumed in a day. And the Solio would do the same for my Ipod which included listening to tunes for a couple of hours on the trail and hour or so of movie viewing each night.

In reality, they didn't even come close. I'm glad I brought extra cells just in case.

If I had been able to simply lay the chargers out in direct sun all day they would have had a chance. And that probably would have been possible had I been base camping somewhere.

But I wasn't and therein was the problem. It was impossible to keep the chargers in direct sun and therefore maximum output while I was on the move. Most of the miles were in forest cover. The panels were mounted on my pack and sometimes my own head shaded them. Deep canyons were too shady. I had to constantly stop and adjust the orientation of the panels when I changed direction. They blocked access to my pack. The whole experiment was a PITA for very little power harvested. After spending all day in the charger the two AAA's moved my GPS's power meter up only one bar of four. I would get a good hour or so of sun on them in the evening when I made camp but only by constantly adjusting as the sun set.

I could build an array twice as big and harvest more power but that would border on impractical because it would cover so much real estate on my pack.

My conclusion: Until more efficient technology arrives, it's simpler, lighter, and cheaper to just carry extra cells. Unless you are out for a very long time, or just staying in one sunny place.

Top
#90879 - 02/21/08 12:47 AM Re: Solar chargers & backpacking [Re: 300winmag]
Dryer Offline
Moderator

Registered: 12/05/02
Posts: 3571
Loc: Texas
Some of us use these for amateur radio charging and operation:
http://www.powerportstore.com/Solar%20Recharging%20-%20AR.htm

Note the backpack cover version. "Battery size adapters" can be built easy enough but some do exist already. A variable voltage regulators are available in postage stamp size using surface mount parts.

As TrailRunner said, solar charging looks good on paper. Constant sun (or lack there of) is the problem, along with keeping the cell array pointed at the sun. If you have the luxery of a sunny day, mounting your solar array on a umbrella might work.

Eric said:
Quote:
I realize few of us "need" this gadget (until it comes on the market, that is!). But let's say we take an existing unit from someone like West Marine or a sea kayak company and try to adapt it to AA, AAA coin batteries of various numbers, and the CR123 batteries in SteriPens, etc., etc. HOW IS THAT DONE??
Obviously different retainers are required for diffrent batteries shapes and sizes but the trickier part is different amperages for different batteries. No?


It's actually quite easy. In backcountry radio I use a 5ah gel cell, 13.8 vdc, for just about everything, or to be really lightweight, a bank of lithium ion batteries like what come in your cell phone, banked to again, 13.8vdc. As long as I know the voltage needs of what I'm trying to power, a simple voltage regulator circuit allows me to vary the voltage of the power supply to run the appliance with a turn of a trimmer pot. That circuit is about 1" in diameter. In the case of your steri-pen, you'll do some minor surgery (yes, the warranty will be voided) to solder leads directly to the positive and negative terminals, out to a battery connector, usually an "Anderson Powerpole" or a molex type. You'll still be able to use internal batteries if done right. The current capability of the battery doesn't matter other than to make sure it will supply the device with at least what's specified.


Edited by Dryer (02/21/08 07:12 AM)
_________________________
paul, texas KD5IVP

Top
#90880 - 02/21/08 03:20 AM Re: Solar chargers & backpacking [Re: Trailrunner]
jshannon Offline
member

Registered: 02/14/06
Posts: 410
Loc: North Texas
Have you tried the crank chargers or pull chargers? I'm not sure if the pull chargers are widely available yet.
_________________________
Ten Essential Groups

Top
#90881 - 02/21/08 06:51 AM Re: Solar chargers & backpacking [Re: 300winmag]
Brumfield Offline
member

Registered: 12/23/07
Posts: 255
Loc: Expat from New Orleans, now in...
Hey Eric, thanks for the heads-up on the up and coming solar gear. I'm considering buying the Sunlinq 12 watt solar charger for recharging my battery packs on my caving and cave diving trips. I was wondering if anyone here has used this model or anything similar to it in the 12 watt output range? Brum

Here's a link to the Sunlinq solar charger:
http://www.backup-power.ca/catalog/item/3393232/3676689.htm
_________________________



Top
#90882 - 02/21/08 10:35 AM Re: Solar chargers & backpacking [Re: Brumfield]
Trailrunner Offline
member

Registered: 01/05/02
Posts: 1835
Loc: Los Angeles
Err...Brum I don't think a solar charger will work too well in a cave <img src="/forums/images/graemlins/blush.gif" alt="" />

OK, I know what you mean but I couldn't help myself <img src="/forums/images/graemlins/smirk.gif" alt="" />

About that charger: Keep in mind that 12 watts is its maximum output under ideal conditions which are different from real world conditions. It may or may not do the job depending on your power requirements. Also its 12V output may or may not be suitable for your needs. Fine if you're charging a 12V battery but lots of equipment is not 12 volts.

I don't know if money is an issue for you or not, but it's not hard to build a very similar device for way less $$$ using thin film solar panels. See my link to Sundance Solar above. All it really takes is some basic soldering skills. Wiring instructions come with the panels.

So simple even a backpacker can do it!!!!

Top
#90883 - 02/21/08 10:49 AM Re: Solar chargers & backpacking [Re: jshannon]
Trailrunner Offline
member

Registered: 01/05/02
Posts: 1835
Loc: Los Angeles
Quote:
Have you tried the crank chargers or pull chargers? I'm not sure if the pull chargers are widely available yet.


No, for the same reasons I'm shying away from solar charging. The weight, bulk, expense and hassle is way more than just carrying a few extra cells. They don't work for my particular style of backpacking.
_________________________
If you only travel on sunny days you will never reach your destination.*

* May not apply at certain latitudes in Canada and elsewhere.

Top
#90884 - 02/21/08 12:21 PM Re: Solar chargers & backpacking [Re: 300winmag]
Eric Offline
member

Registered: 09/23/02
Posts: 294
Loc: The State of Jefferson
I've done several solar powered trips and some have worked out better than others. Charging while on the move is a bust unless you're in a treeless area and heading more or less north since as Trailrunner said you block the panel with your head and hat. I did try putting a small panel on my hat but that was just too annoying and it was too small to be much use. A larger panel did work well on trips where I had lots of time in a camp with sun exposure near by. That was using a 5w panel with a bit of electronic circuitry to bring the voltage down and the current up to match the battery. That was fine for a Palm TX, a camera and some AA cells. The weight is too high for short trips but past 4 or 5 days, depending on you power requirements, it starts making sense.

Top
#90885 - 02/21/08 12:45 PM Re: Solar chargers & backpacking [Re: Eric]
Trailrunner Offline
member

Registered: 01/05/02
Posts: 1835
Loc: Los Angeles
Maybe this will be the answer when the bugs are worked out.
_________________________
If you only travel on sunny days you will never reach your destination.*

* May not apply at certain latitudes in Canada and elsewhere.

Top
#90886 - 02/21/08 02:14 PM Re: Solar chargers & backpacking [Re: Trailrunner]
coyotemaster Offline
member

Registered: 03/07/06
Posts: 294
Loc: Arizona
Why can't solar panels be mounted on an umbrella?
Or use carbon fiber rods
to construct an umbrella like frame over your head & your pack to hold the
solar panel/films.

Top
#90887 - 02/21/08 02:22 PM Re: Solar chargers & backpacking [Re: coyotemaster]
Trailrunner Offline
member

Registered: 01/05/02
Posts: 1835
Loc: Los Angeles
Quote:
Why can't solar panels be mounted on an umbrella?
Or use carbon fiber rods
to construct an umbrella like frame over your head & your pack to hold the
solar panel/films.


A fine idea....as long as you're not walking in the shade, or on a cloudy day, or in a deep canyon, or on a windy ridge.
_________________________
If you only travel on sunny days you will never reach your destination.*

* May not apply at certain latitudes in Canada and elsewhere.

Top
#90888 - 02/21/08 05:38 PM Re: Solar chargers & backpacking [Re: OregonMouse]
wandering_daisy Offline
member

Registered: 01/11/06
Posts: 2751
Loc: California
Last year I was able to do 12 days with over 250 pictures on one battery. I think it depends a lot on exactly what camera you have. With my old camera I had to take a spare battery. But the camera battery is really light weight - it just is expensive to get a second one. You might consider getting a new camera.

I also am very careful not to do anything but take photos - no looking at them at night! I also sleep with my camera if I want early morning photos. I have found that when apparantely "dead" the camera does fine once I warm it up. My camera has a metal case and quickly gets cold.

I do not take extra batteries on a backpack. I do not use a GPS, I hardly ever use my head lamp, do not take a cell phone. I probably would not take these items even if someone came up with a light-weight solar charger.

I use passive solar energy as I can - pre-heat my water bottles before cooking and washing, melt snow, set up camp in a location to get early morning light to dry the tent. I do not go out in the wilderness to replicate civilization.

Top
#90889 - 02/21/08 05:52 PM Re: Solar chargers & backpacking [Re: wandering_daisy]
Trailrunner Offline
member

Registered: 01/05/02
Posts: 1835
Loc: Los Angeles
Just to expand on WD's post, I found that I get much more life out of my camera battery if I turn off the LCD screen and use only the optical viewfinder. I also turn off the auto review feature, which momentarily displays each shot on the LCD screen after it is taken.

And I also resist the temptation to review my work every night.
_________________________
If you only travel on sunny days you will never reach your destination.*

* May not apply at certain latitudes in Canada and elsewhere.

Top
#90890 - 02/21/08 08:31 PM Re: Solar chargers & backpacking [Re: Trailrunner]
Brumfield Offline
member

Registered: 12/23/07
Posts: 255
Loc: Expat from New Orleans, now in...
Trailrunner wrote:
Err...Brum I don't think a solar charger will work too well in a cave <img src="/forums/images/graemlins/blush.gif" alt="" />

OK, I know what you mean but I couldn't help myself <img src="/forums/images/graemlins/smirk.gif" alt="" />

About that charger: Keep in mind that 12 watts is its maximum output under ideal conditions which are diferent from real world conditions. It may or may not do the job depending on your power requirements. Also its 12V output may or may not be suitable for your needs. Fine if you're charging a 12V battery but lots of equipment is not 12 volts.


Brumfield wrote:
Yeah, Kevin, I know what you mean. <img src="/forums/images/graemlins/smirk.gif" alt="" /> I promise to only cave in Waitomo if I need to recharge while still under ground. See how I glow wormed my way out of that one!


To charge (outdoors, above ground, during daylight <img src="/forums/images/graemlins/smirk.gif" alt="" />) my AAA, AA, C, D, and 9V batteries that power up my video, cave, and dive lights, the 12 watt solar cell will be run through my Accu-manager 20 charger which has a cigarette lighter type male adapter (12 volt). Yes, you can run 12 volt items straight off the solar panel with no charger or adapters needed.

The ads state it will charge at a maximum rate of 700m and will charge AA batteries in 3 hours. Didn't say how many batteries at one time. I was wondering if anyone had real world experience with this unit. As you know, ad hype is not always trustworthy. Brum
_________________________



Top
#90891 - 02/21/08 10:29 PM Re: Solar chargers & backpacking [Re: 300winmag]
NiytOwl Offline
member

Registered: 11/06/04
Posts: 501
Loc: California
Having made a solar-cell hat, I can tell you there are a lot of problems with photovoltaics on the trail:

1. Partial shading of the panel results in greatly reduced output. Basically, if you shade out a cell it presents a high resistance to the rest of the panel. To combat this, you must subdivide the array into many smaller panels - each a complete solar battery. Then if part of the array is shaded the remaining panels are still providing the full output voltage at reduced current.

2. As was pointed out earlier, unless you're hiking in the desert or above treeline, you'll probably be in the shade quite a bit.

3. If you stop for a while, you might find a sunny place for your panel. You need a panel that has enough capacity to charge your batteries in a short time (who wants to waste a day to charge batteries?). Said panel therefore needs to be high wattage and will be, from an ultralight standpoint, heavy (2+ pounds).

This goes back to what Dryer said - take one big battery to charge all your little ones. You can buy lithium polymer packs with high capacities for less than an equivalent solar panel. An 11 Ah @ 6V pack weighs under a pound and will charge all your gear with the appropriate charger. My PDA/phone, gps module, and AA/AAA battery charger all use a mini-usb jack at 5V. This simplifies things since I only need one charger. The only exception would be CR-123 batteries - and they're light enough to just bring extras.

Very few of us hike for more than a week without hitting a town or a cache. Consider this an opportunity to replace or recharge your battery pack.

I know solar sounds like the "green" thing to do, but sometimes it doesn't make sense when other technologies are more convenient and can do the job with less weight.

BTW, there are many companies that sell "roll up" solar panels. Here's one with grommets.

Top
#90892 - 02/21/08 11:57 PM Re: Solar chargers & backpacking [Re: Brumfield]
NiytOwl Offline
member

Registered: 11/06/04
Posts: 501
Loc: California
Brum, the rule of thumb I learned for battery charging is

( 1.5 x batt. capacity ) / charge rate

This assumes that battery is fully discharged. It always takes more energy to charge a battery than you get back out. The extra energy shows up as heat (battery gets warm).

For 2300 mah NiMH cells, and a charge rate of 700 mah, that's 4.9 hours. 3 hours may be for charging some old 1500 mah cells or possibly NiCd cells.

As far as converting your 12V, 1A output to what you need - there are many variable switching power supplies available. They take 12V and convert it to any other standard DC voltage. They're small and light - look at the charger for a cell phone for an example.

Top
#90893 - 02/22/08 07:19 AM Re: Solar chargers & backpacking [Re: NiytOwl]
Dryer Offline
Moderator

Registered: 12/05/02
Posts: 3571
Loc: Texas
Here's my cheapo setup. That mini- Altoids tin has a voltage regulator circuit I built and what you can't see is a trimmer pot connecting pins 2 and 3 of the chip to make it variable. I've premarked points on the pot to match other device voltages. I could make it smaller but the thing weighs about an ounce as it is. The pictured battery is a 12vdc, 1.4ah gel cell that will last me a week of 1 watt transmitter time, and charge other devices as well. That battery costs about $6 and is basically a chunk of lead in weight, but is very forgiving with respect to charging scheme. Lithium batteries are much lighter, way more expensive, and a bit more picky about how they are charged. All my lithium batteries are salvaged from cell phones, however. Anyway, like you said NiytOwl, most of the time we aren't out that long and this setup is lighter than a solar array and much more reliable. I've never lost a coin cell or run one down in my led light, and I don't bother with hauling extras. My stuff is designed around remote amateur radio operation. A system could easily be optimized based on specific hiker needs and weight cut to a minimum.

_________________________
paul, texas KD5IVP

Top
#90894 - 02/22/08 10:26 AM Re: Solar chargers & backpacking [Re: OregonMouse]
Cloudy Offline
member

Registered: 01/24/05
Posts: 185
Loc: Central California
If your camera can use AA Lithium batteries, I recommend them highly. I get MUCH more life out of a set - perhaps as much as 50% more photos as opposed to rechargeables or Alkalines in my Canon A710IS. They are also lighter than either of the above but are much more expensive.

Alan

Top
#90895 - 02/22/08 12:13 PM Are you KIDDING me? HA! [Re: Trailrunner]
300winmag Offline
member

Registered: 02/28/06
Posts: 1342
Loc: Nevada, USA
WOW! A knee-powered charging unit. What next? Flatulence-powered stoves?

Geeze Oh MAN (as Radar O'Rielly used to say) I never expected this much response to such a geeky question. Thanks everyone.

I've decided that, even though I do backpack in the southwest, I'll just carry extra Lithium batteries. The state of solar panels tech right now is not where it seems practical for backpacking. Maybe in a few years a 25 watt panel will be as small as a present day 5 watt panel and much more efficient in overcast conditions.

Eric
_________________________
"There are no comfortable backpacks. Some are just less uncomfortable than others."

Top
#90896 - 02/22/08 12:45 PM Re: Lithium batteries in Canon A710 camera [Re: Cloudy]
OregonMouse Offline
member

Registered: 02/03/06
Posts: 6400
Loc: Gateway to Columbia Gorge
Cloudy, I have the same camera as you (Canon A710IS) and the instruction book says not to use lithium batteries. Otherwise I'd already be using them! How long have you been using lithium batteries in yours, and have you had any problems? Does anyone else have this camera (or an earlier similar model such as the Canon A510) who uses lithium batteries? It uses two AA's. I think I can turn off the LED screen and use the viewfinder, but I haven't yet figured out how to do that (I'm still working my way through the instruction book), and if I can figure it out I will do so for longer trips.

I do use lithium batteries in my headlamp--I ditched my Petzl and bought a Princeton Tech so I could do so. I can't do that with the camera because it's new, it was a joint present from my children and it does take great pictures.


Edited by OregonMouse (02/22/08 12:54 PM)
_________________________
May your trails be crooked, winding, lonesome, dangerous, leading to the most amazing view--E. Abbey

Top
#90897 - 02/22/08 01:01 PM Re: Lithium batteries in Canon A710 camera [Re: OregonMouse]
Cloudy Offline
member

Registered: 01/24/05
Posts: 185
Loc: Central California
Lol. I've been using them for perhaps six months. I haven't had any problems as of yet but now that you've let the genie out of the bottle by saying that they're not recommended for the A710IS (I must have missed that), I'm expecting it... :-) In my case, the camera is a remanufactured one which didn't cost full price so the risk is acceptable. I'll be replacing it sometime in the near future with the A720IS anyway.

Alan

Top
#90898 - 02/23/08 04:07 PM Re: Batteries in Canon A710 camera [Re: Cloudy]
OregonMouse Offline
member

Registered: 02/03/06
Posts: 6400
Loc: Gateway to Columbia Gorge
I just went into the Canon website. It claims that by using rechargeable AA NiMH batteries with the A710IS, you can take 360 shots per set of batteries vs. 100 shots on AA Alkaline batteries, with the LED screen on. If this is anywhere near correct, I should be able to charge 3 sets of batteries (1 fresh pair in the camera and 2 spare) at home for an 8-9 day trip. I could probably get along with 2 pair if I keep the LED screen off most of the time (it's pretty useless in bright light anyway). This is a lot more reasonable than a pair of batteries per day and means a lot fewer batteries in the trash. I hadn't realized there was that much difference between the alkaline and rechargeble batteries. Needless to say, I will check this out very thoroughly before risking running out of batteries at the most scenic portion of a long trip!

Any further advice or comments are most welcome!
_________________________
May your trails be crooked, winding, lonesome, dangerous, leading to the most amazing view--E. Abbey

Top
#90899 - 02/23/08 05:08 PM Re: Batteries in Canon A710 camera [Re: OregonMouse]
Pika Offline
member

Registered: 12/08/05
Posts: 1735
Loc: Rural Southeast Arizona
OM,
I just bought a set of AA Lithium ion batteries for my Canon digital. They sell them at WalMart and Target so they are easy to get. The Li cells weigh 0.52 oz each compared with 0.86 oz each for the alkaline cells and about 1.00 oz each for the NiMH cells. They are also supposed to last "seven times longer than alkaline batteries in digital cameras". I have some in my camera now and will let you know how they work out.
_________________________
May I walk in beauty.

Top
#90900 - 02/23/08 05:47 PM Re: Batteries in Canon A710 camera [Re: OregonMouse]
Trailrunner Offline
member

Registered: 01/05/02
Posts: 1835
Loc: Los Angeles
All AA NiMH cells are not created equal. Some have higher capacity than others. Read the packaging or labels and try to find a capacity of 2500 mAH or better. Some old AA cells with 1600 mAH capacities are still being sold out there. That's considerably lower.

One downside to NiMH chemistry is the high self discharge rate. Your freshly charged cells will lose about 10-15% of their capacity in 9 days. The new Sanyo Eneloop NiMH cells claim a far lower self discharge rate for a little more money. In my experience their claim seems to be valid.

Invest in a good quality "smart" charger. Avoid cheap "dumb" chargers that rely on only a timer for a fixed charge time regardless of the cell's state of discharge. Some don't even have a timer and will fry your cells very quickly if left in too long. The better chargers rely on the cell's voltage, temperature or both to terminate the charge cycle. The better chargers will also ensure that you leave home with fully charged cells by not terminating the charge cycle until the "tank" is full. Some cheaper chargers may terminate before the cell is fully charged. And some older chargers are not designed to fully charge the newer high capacity cells.

Buy your cells well before you leave and run them through several charge/discharge cycles. This breaks them in and even slightly increases their capacity. This practice also reveals the dud cells, which are not terribly uncommon with some brands.

I have found Thomas Distributing to be a good online source for cutting edge cells and chargers. Their website will show you what's out there even if you don't buy from them.

360 shots with the LCD screen on sounds very optimistic to me. Maybe with freshly charged (same day) high capacity cells, no flash, no timer and no auto preview, but I would not rely on that figure.

Top
#90901 - 02/23/08 06:03 PM Re: Batteries in Canon A710 camera [Re: Pika]
Trailrunner Offline
member

Registered: 01/05/02
Posts: 1835
Loc: Los Angeles
Pika, the risk of sounding picky, if those AA's you bought were primary (non-rechargeable) cells they were not Lithium ion , just Lithium. There is a difference. There are true Lithium ion rechargeable cells in AA form but their voltage is much higher. Li-ion chemistry is what you will see in most cell phone and proprietary rechargeable camera batteries.

Sorry to be so darn nikpicky but this stuff is my hobby <img src="/forums/images/graemlins/tongue.gif" alt="" />

Top
#90902 - 02/23/08 09:36 PM Re: Batteries in Canon A710 camera [Re: Trailrunner]
OregonMouse Offline
member

Registered: 02/03/06
Posts: 6400
Loc: Gateway to Columbia Gorge
Thanks, Trailrunner, I thought that the Canon website info sounded too good to be true! And thanks for all the great tips and for the site reference for Thomas Distributing. I'll get a charger and some rechargeable batteries (better for around home, anyway) and do a bunch of experimenting. That's disappointing that they lose juice over time! I'll get the batteries you recommended.

In the meantime, I'll spend a lot more time with the instruction book and learn how to turn off the LED screen. As I mentioned, it's useless in sunlight anyway. The viewfinder isn't all that great (smaller area than the actual picture) but I can crop once I've uploaded the images to my computer.

In the meantime, back to the original topic--we'll all wait for a solar recharger that works! If anyone can invent a nice lightweight one, I will be one of the earliest in line!


Edited by OregonMouse (02/23/08 09:56 PM)
_________________________
May your trails be crooked, winding, lonesome, dangerous, leading to the most amazing view--E. Abbey

Top
#90903 - 02/25/08 01:37 PM Re: Batteries in Canon A710 camera [Re: OregonMouse]
Earthling Offline
member

Registered: 02/22/03
Posts: 3228
Loc: USA
Costco sells the Sanyo batteries with the charger. I saw them the other day when I was out there on a trip.

If the thin film technology is ever used correctly by an outdoor gear minded manufacturer; then a folding soalr panel would be nice. It could fold to the size of a deck of cards for packing, then unfold open to the size of a 2 x 2 ft square or something. That's my dream and I'm sticking to it.....much closer than say 25 years ago <img src="/forums/images/graemlins/blush.gif" alt="" />
_________________________
PEPPER SPRAY AIN'T BRAINS IN A CAN!

Top
#90904 - 02/25/08 03:27 PM Re: Batteries in Canon A710 camera [Re: Trailrunner]
Cloudy Offline
member

Registered: 01/24/05
Posts: 185
Loc: Central California
Quote:

One downside to NiMH chemistry is the high self discharge rate. Your freshly charged cells will lose about 10-15% of their capacity in 9 days. The new Sanyo Eneloop NiMH cells claim a far lower self discharge rate for a little more money. In my experience their claim seems to be valid.


This is what prompted me to switch to Lithium disposables. I couldn't believe how quickly the Eveready 2500 mah cells discharged simply by sitting unused in my camera. I wonder if they would discharge any quicker in colder weather.

Alan

Top
#90905 - 02/25/08 08:23 PM Re: Batteries in Canon A710 camera [Re: Cloudy]
Franco Offline
member

Registered: 04/05/04
Posts: 997
Loc: Australia
Yes the Eneloop are the way to go. Using a Canon A510 I gave up testing it after having taken more than 500 shots over several weeks. The Eneloop will keep the voltage at just over 1 volt till the end, this is the minimum required by most digital still cameras. They also work well under freezing point.
Franco

Top
Page 1 of 2 1 2 >

Shout Box

Highest Quality Lightweight Down Sleeping Bags
 
Western Mountaineering Sleeping Bags
 
Lite Gear Talk - Featured Topics
Knife, Fire Starter, Ignition Source
by Jim M
Yesterday at 07:34 PM
Bivvy bag with wired peak
by Petro1234
12/10/17 01:06 PM
How cheap can you go?
by EMT Dave
12/05/17 07:07 PM
Backcountry Discussion - Featured Topics
Greetings - and a question
by valongi
Yesterday at 11:35 AM
Just found out about UCO candles
by toddfw2003
11/30/17 08:41 AM
Hitting the eagle rock loop, Ark in 3 days
by toddfw2003
11/19/17 11:31 AM
Make Your Own Gear - Featured Topics
Plant based insulation...
by billstephenson
11/18/17 02:58 PM
lightest grommets to use
by toddfw2003
10/22/17 06:13 PM
avalibility of thin ti rod
by the-gr8t-waldo
01/26/17 04:45 PM
Featured Photos
Breakneck Ridge, New York
May 2012 Eclipse, Lassen Park
New Years Eve 2011
Trip Report with Photos
Seven Devils, Idaho
Oat Hill Mine Trail 2012
Dark Canyon - Utah
Who's Online
0 registered (), 24 Guests and 0 Spiders online.
Key: Admin, Global Mod, Mod
Newest Members
valongi, Atkinson J, Dcarpenter, Woodland, ultralight
12469 Registered Users
Forum Links
Disclaimer
Policies
Site Links
HOME
Backpacking.net
Family Hiking
Lightweight Gear Store
Backpacking Book Store
Lightweight Zone
Hiking Essentials

Outdoor Gear Daily Deals
Outlets, Sales, Bargains

Our long-time Sponsor, BackcountryGear.com - The leading source for ultralite/lightweight outdoor gear:

Backcountry Forum
 
 

Since 1996 - the Original Backcountry Forum
Copyright © The Lightweight Backpacker & BackcountryForum.com