solar/ battery charging.^

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trigger
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solar/ battery charging.^

Post by trigger » Sat Sep 15, 2012 12:39 am

There are heaps of bits on the market like power monkeys, that should be good to charge tech, but what are you guys using to recharge gps/vhf/ mobile/kindle etc...... cos surely spare batteries are only an option for overnight trips???

derek wade
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Re: solar/ battery charging.

Post by derek wade » Sat Sep 15, 2012 12:07 pm

From Midget599.
Interesting question ,Trigger you must have been reading my mail!!I shall be undertaking a long trip next year and the question arises how do I re-charge my hand held vhf. and mobile phone without making landfall.Is there anything out there in the market place with the answer??

rockhopper
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Re: solar/ battery charging.

Post by rockhopper » Sat Sep 15, 2012 4:36 pm

Just clubbed together and got my mate one of these for his birthday. Not had the chance to try it in anger yet but it certainly looks the business:
http://biolitestove.com/campstove/camp- ... /features/

Rog.

CharlieS
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Re: solar/ battery charging.

Post by CharlieS » Sat Sep 15, 2012 6:47 pm

I've got one of the biolite stoves. I think it's a great bit of kit, but not the solution for charging a vhf.
Mine didn't come in time to be tested on a kayaking trip but it came with us on a family camping trip.
It's a great stove. The battery and fan makes it easy to light and it produces a lot of heat. We used it as much as the gas burners we had with us to cook and boil water. It needs some dry fuel to light it but it's nowhere near as fussy as a kelly kettle.

I haven't done loads of testing on how well it charges but it seems to be the kind of thing you'd use to recharge your phone in an emergency to make a few short phone calls, rather than something you'd use daily to charge a vhf. To get lots of charge out you'd need to keep feeding it fuel for a long time, and probably into a forgiving secondary battery that you can then use to charge the actual item of kit. (The charge tends to start and stop which confuses some phones into thinking it's not worth trying to get any more charge.)

I would recommend the stove. It's great fun. The kids love it. It feels good not to be spending money on fuel in metal bottles when you can collect it for free as you go. Unlike a kelly kettle you can genuinely cook over it like a stove. Unlike a camp fire you need very little fuel. It also does a bit of charging that could get you a crucial phone call in an emergency or light a lamp while you cook. You also feel like your yuppy spending has helped them develop a product for the third world.

Time will tell how robust the electronics are.

Charlie

trigger
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Re: solar/ battery charging.

Post by trigger » Mon Sep 17, 2012 8:13 pm

Ha that's really cool, but alas not the thing.......I need waterproof/ storm proof solar.......I think.

ruralweb
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Re: solar/ battery charging.

Post by ruralweb » Mon Sep 17, 2012 8:28 pm

I have tried them all - power monkeys, solar gorrillas etc etc and they are rubbish IMO, I sent them all back and got refunds. They all need many hours of direct sunlight to charge so you would need to leave them on deck while you paddle - they are NOT waterproof so will be trashed the first time it rains or you get a wave over them. Plus its never really light enough for them to charge fully - I managed to run an iphone for a week on one BUT it was one to those weeks where we had clear blue skies all day and I needed to keep the solar panel facing the sun. In reallity its going to be overcast and when you really need it its going to be dark and raining so its useless.

I spoke at great length to the makers of several of these things and they admitted they are designed really for places like deserts and non of them have been really tested for being waterproof - they are water resistant which means a couple of drops of water. So any ideas about attaching them to the deck of a kayak is unrealistic.

I have ended up using the 12v battery out of a car jump starter - it has a very high capacity and is relatively small BUT its heavy. With this I can run 2 iphones, 2 VHF radios and a tent light for 25 days, I keep it in a dry bag so its waterproof and use standard 12v car chargers to convert the power. You can get smaller lead acid batteries from Maplins or if your rich use a Lithium battery which is lighter and smaller.
Mal

Chris Bolton
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Re: solar/ battery charging.

Post by Chris Bolton » Mon Sep 17, 2012 8:38 pm

I bought one of these http://www.mobile-energy2.com/product_foldable650.php a few months ago and used it for 2 weeks in Greenland. It was good for charging phones and gps, provided you had the right charger. The panel produces 12v and comes with a car lighter socket and a USB output, but I found the USB output didn't work with all 5v devices, some required me to use a specific USB charger in the socket. Greenland was a good place to use it, 20hrs of daylight and not much cloud, I haven't yet tried it on a trip in the UK. Folds up well and was happy stuffed in a drybag. I didn't try using it on the boat as I hadn't set up water resistant connectors for my devices and while it claims 'water resistant' it says not to submerge it so it may not have been too happy on deck. I also found it worked best if you pointed it to face the sun - probably within 15º was as good as facing, further then that the performance reduced.

It doesn't seem to be available any more and perhaps has been replaced by a 5v specific http://www.me2solar.com/aurora-4.html and a larger 12v version http://www.me2solar.com/aurora-pro12

The CIGS panel technology seems to be a step forward compared to the older panels.

Chris

StewartR
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Re: solar/ battery charging.

Post by StewartR » Mon Sep 17, 2012 8:58 pm

trigger wrote:There are heaps of bits on the market like power monkeys, that should be good to charge tech, but what are you guys using to recharge gps/vhf/ mobile/kindle etc...... cos surely spare batteries are only an option for overnight trips???
Hi Trigger

Solving the logistics of keeping electrical items with power starts before you buy your kit in the first place. Everything comes with different voltages and different charging attachments. Hopefully the decision -making examples below will help:

VHF
We deliberately chose the ICOM M1 EuroV (now replaced by the M71) 8 years ago because it has long battery life. Each year Debbie and I go on a 3 week trip somewhere. My VHF is typically switched on when paddling. The battery easily lasts the full trip (approximately 16 days usage). Admittedly, I rarely make calls, which undoubtedly helps. We did buy a second battery pack for it but have never had to use it. I reckon I may have power for 6-8 weeks usage without recharging. If I was ever replacing my VHF, battery life would be a major consideration. I would probably never buy one with a DSC GPS function unless it could be switched off for longer trips.

GPS
Our GPS is a simple one without screen (screens and GPS consume batteries). It is virtually never switched on. Even on longer crossing when our destination is visually obscured we put our destination coordinates into the GPS just in case, but switch it off. We prefer to navigate by looking at the landscape and maps; or following a bearing and using dead-reckoning rather than looking at a screen. Consequently GPS battery life is never an issue.

PLB
We carry a SPOT PLB. We principally carry it for emergency use. We however switch it on to send OK messages (with our location) to relatives (sort of like a satellite postcard). Battery life is therefore not an issue.

Cameras
Photographs are important to us. We carry three cameras (2 waterproof and one for on land). We carry a small stash of replacement rechargeable batteries for each. This costs, but is cheap when compared to the need to buy film in days gone bye for each trip. GPS functions are always switched off.

Mobile Phone
Our mobile phone is only used to get weather forecasts twice a day (when available). It is not used for any other purpose. Some web sites only work on smart phones therefore I have an HTC Explorer. Its battery life is much better than many other smart phones, but I have enabled all the power saving functions including turning off GPS and reducing screen brightness. It is not programmed to get my emails either. With all this done, and switching it off between uses, I get perhaps 6 days of battery life. When a phone searches for signal that doesn’t exist it uses a lot of power. This year we got a Power Monkey Explorer (solar charger & battery pack) to recharge the phone whilst in Greenland. I was impressed. Admittedly we had two weeks of sunshine, but I was never short of power and finished the trip with both the phone and Power Monkey fully charged .

Weather Radio
When in the US we carry a weather radio. Our radio takes big C or D size batteries and easily lasts a trip.

Books
Paper never loses its charge!

So, there are many options. However what I would urge you to do is consider battery life and recharging when deciding what kit to buy.

Regards

Stewart

ruralweb
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Re: solar/ battery charging.

Post by ruralweb » Mon Sep 17, 2012 10:46 pm

I agree that selecting devices that require minimal power is a prime consideration and I would love to be able to cut my power usage but I need to have my iPhone on all the time so I pay the price in terms of weight. It's a trade off at the end of the day - if your heading somewhere with lots of sun then a solar system will work but if its a typical week in UK then I would stick with a battery. The power money's etc have a small mains charger so if your calling at pubs etc then you can top them up while you have a pint.
Mal

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atakd
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Re: solar/ battery charging.

Post by atakd » Tue Sep 18, 2012 8:25 am

ruralweb wrote:
I have ended up using the 12v battery out of a car jump starter - it has a very high capacity and is relatively small BUT its heavy. With this I can run 2 iphones, 2 VHF radios and a tent light for 25 days, I keep it in a dry bag so its waterproof and use standard 12v car chargers to convert the power.

I agree that a small lead acid battery is the best way to go. I struggled to charge a phone over a week in Brttany in May with a 10W panel - it never fully charged it.
What is the Ah rating of your battery? I've been looking at a 12Ah battery http://tinyurl.com/8d46nkr for 3-4 days recharging of GPS, VHF and phone. Do you think this would be big enough?
Andy

PSK
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Re: solar/ battery charging.

Post by PSK » Tue Sep 18, 2012 9:07 am

I looked into just this topic before I set out on the UK circumnavigation trip, with an aim to charge AA (GPS) batteries, VHF battery and smartphone (Blackberry) battery over the prolonged time away.

For me I could not find a commercial product that provided sufficient ouput, waterproofing and realistic size so I went down the self manufacture line. It was fairly easy and relatively cheap to put together a solar charging circuit. However there were snags of course; the output/charging rate has to be limited to prevent damage to the batteries. This in turn means that the charging takes many hours - sat on the shore. But obviously the time when the sun is out is also paddling time, so the obvious answer would seem to be to be to mount the panels on to the boat. But reliable waterproofing was a problem and the output of the panels is critically dependent on facing and angle towards the sun; output drops off quickly if not correctly aligned and neither were easily maintained whilst afloat. After a few weeks of messing around I realised it just wasn't a realistic or reliable proposition.

So for me in the end the easy and obvious answer was to carry plenty of spare batteries - the Blackberry batteries were cheap and only 20g apiece - you could carry quite a few of these before they matched the weight or cost of a commercial solar charger. The GPS AA batteries could be sourced easily and so only a few had to be carried and I took a couple of spare batteries (plus an AA battery cradle) for the Standard Horizon VHF , which was very gentle on battery life.

As is often the case, the marketing man's gadgets lost out to simplicity.

JW

ruralweb
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Re: solar/ battery charging.

Post by ruralweb » Tue Sep 18, 2012 2:26 pm

What is the Ah rating of your battery? I've been looking at a 12Ah battery http://tinyurl.com/8d46nkr for 3-4 days recharging of GPS, VHF and phone. Do you think this would be big enough?
Mine is 25Ah so the one you are looking at would easily do 4 days IMO - perhaps you could get away with an even smaller one, I was looking at getting a 5Ah for shorter trips but never got round to it.

As JW says batteries for a Blackberry are the way to go - it lasts for many days on each. iphones however are real power eaters and need charging every day if your using them for calls, GPS and charts so which battery will also depend on how power hungry your kit is - its a bit like Apollo 13. Im tall so have a big kayak and lots of space!

PS John, I followed your blog everyday - brilliant!
Mal

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atakd
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Post by atakd » Tue Sep 18, 2012 5:39 pm

My concern with buying extra specific batts is the restrictions they place on different devices - especially if paddling with someone else with different phone/VHF whatever.

Thread Drift:
ruralweb wrote:
PS John, I followed your blog everyday - brilliant!
@ PSK Had a look at the blog - were you surfing at New Brighton on Friday or Saturday or thereabouts? Saw 2 distinctive red/white kayaks on the beach when cycling past.
Andy

ruralweb
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Re: solar/ battery charging.

Post by ruralweb » Tue Sep 18, 2012 9:14 pm

My concern with buying extra specific batts is the restrictions they place on different devices - especially if paddling with someone else with different phone/VHF whatever.
that's why I went for a 12v system - I just wired in a 12v female car socket and use car adapters to charge stuff. So anyone I'm paddling with can use the battery if they bring thier car charger
Mal

StewartR
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Re: solar/ battery charging.

Post by StewartR » Tue Sep 18, 2012 9:40 pm

ruralweb wrote:Mine is 25Ah so the one you are looking at would easily do 4 days IMO - perhaps you could get away with an even smaller one, I was looking at getting a 5Ah for shorter trips but never got round to it.
Am I missing something? I googled 12v 25ah lead acid battery and they weigh 11-15kg.

Puzzled,

Stewart

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atakd
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Re: solar/ battery charging.

Post by atakd » Tue Sep 18, 2012 9:48 pm

StewartR wrote:
ruralweb wrote:Mine is 25Ah so the one you are looking at would easily do 4 days IMO - perhaps you could get away with an even smaller one, I was looking at getting a 5Ah for shorter trips but never got round to it.
Am I missing something? I googled 12v 25ah lead acid battery and they weigh 11-15kg.

Puzzled,

Stewart
dunno about 25ah but 12ah is 3.7kg,
Andy

StewartR
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Re: solar/ battery charging.

Post by StewartR » Tue Sep 18, 2012 10:07 pm

atakd wrote:dunno about 25ah but 12ah is 3.7kg,
Found a 12v 24ah SLA at 8.5kg. I think I'll stick with my HTC Explorer and Power Monkey Explorer combo. The Power Monkey (power pack and the wee solar panel) only weigh 165g!

Regards

Stewart

ruralweb
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Re: solar/ battery charging.

Post by ruralweb » Tue Sep 18, 2012 10:49 pm

5.2kg - it's heavy yes but I'm not so heavy so it balances out. I'd rather carry my battery than 5kg of excess fat!
It's like many sports I've done loose body weight to gain performance - one of the guys I paddle with weighs 18 stone he has to watch every kg he puts in his boat while I can take what I want ie big tent, nice warm sleeping bag, plenty of water and my car battery! Needless to say he charges his phone using my battery
Mal

ruralweb
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Re: solar/ battery charging.

Post by ruralweb » Tue Sep 18, 2012 11:12 pm

If money is no object and you want a 22ah battery which is very light and compact then these are possibly the answer http://www.deben.com/lithium-ion-batter ... -pack.html at 1.2kg they are a fifth of the weight of mine.
Mal

srod
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Re: solar/ battery charging.^

Post by srod » Wed Sep 19, 2012 5:11 pm

Another alternative - you could make up a pack of standard Alkaline D cells. Much higher energy density than lead acid, much safer and cheaper than lithium-ion.

A bank of 9 would give you 12V, at around 18Ah, weigh just over a kilo, and cost about a tenner.

NathanE
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Re: solar/ battery charging.^

Post by NathanE » Wed Sep 19, 2012 5:49 pm

Another alternative again would be to make a 12v li-ion pack. Look on eBay for 3.7v 18650 li-ion cells from hong kong. I've used ultra fire brand historically. These are the cells used in laptop packs and they come with simple wall wart chargers for pretty good prices. you can easily get 2.2AH cells and some claim higher capacity.

Build a battery holder that will stack one or more parallel sets of three cells in series to get as much 12v output as you desire. I pack mine into a bike water bottle to make it splash proof. I use it for mega lighting power for night riding off road but I guess it would be good to charge stuff too.

ruralweb
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Re: solar/ battery charging.^

Post by ruralweb » Wed Sep 19, 2012 6:15 pm

Thanks for the info guys - I can see a winter project on redesigning my power system!!
Mal

trigger
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Re: solar/ battery charging.^

Post by trigger » Wed Sep 19, 2012 9:03 pm

Really good food for thought guys, cheers!

GrahamKing
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Re: solar/ battery charging.^

Post by GrahamKing » Wed Sep 19, 2012 10:53 pm

NathanE wrote:Build a battery holder that will stack one or more parallel sets of three cells in series...
Are you sure about this? I thought that Li-ion cells (and NiCads) should not be connected in parallel owing to their very low internal resistance. The reasoning was that if a partially discharged cell is in parallel with a fully-charged cell, a very large current will flow, creating a risk of fire or cell rupture. I'm sure that the forum must include someone who can give an expert, informed, opinion on this...

Ken_T
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Re: solar/ battery charging.^

Post by Ken_T » Thu Sep 20, 2012 8:26 am

Hi,
As an engineer I would advise against paralleling most modern battery technologies due to low internal resistance. If you need more capacity if you make up series stacks to about 1V more than the required output voltage & connect a diode at the top of each stack the outputs of the diodes can then be connected together as the diode will prevent reverse current flow. Each stack will then need to be charged seperately, or an additional charging circuit added (which could be as simple as a diode & resistor for each stack if you are not intending to monitor the stack voltage during charging).
Ken

Ken_T
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Re: solar/ battery charging.^

Post by Ken_T » Thu Sep 20, 2012 8:36 am

Hi,
Just an additional thought, you may be better off with several lower capacity stacks as the weight would be the same, you would have no problems wiring protection diodes, but you would have the advantage that you would know how quickly you are getting through your capacity by counting the discharged stacks (assuming you number the stacks so you discharge them in turn).
Ken

NathanE
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Re: solar/ battery charging.^

Post by NathanE » Thu Sep 20, 2012 10:09 am

Thank you, good safety refinement, sounds like I've maybe been lucky but will redo my stacks. Still li-ion much lighter than lead acid and not too expensive nowadays if DIY.

ruralweb
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Re: solar/ battery charging.^

Post by ruralweb » Mon Feb 04, 2013 8:36 pm

After doing some more looking about I have decided on a 10Ah Lion battery from Maplins of all places - http://www.maplin.co.uk/10000mah-portab ... ces-625352

Ive run my iphone off it for 7 solid days - with normal use ie calls, texts, browsing etc and left it on 24/7 so if its turned off at night and with a bit of power saving then 10 days should be easy. Ive ordered another and will strap them together to make 20Ah which is what my lead acid was BUT this only weighs 330g and is much smaller and lighter than the lead acid battery. Charges using an iphone charger or car charger and I have a small solar cell that will plug in so can make use of any sun as well.
Mal

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PhilAyr
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Re: solar/ battery charging.^

Post by PhilAyr » Mon Feb 04, 2013 9:56 pm

ruralweb :
Ive ordered another and will strap them together to make 20Ah
I take it you mean in parralel and not in series. If you put them in series you will double the output voltage. Not a good idea ! In parralel you will double the capacity but not the output voltage. Anyhow the over current protection circuitry inside the lithium - ion battery could kick in and prevent you from doing that. I would use them separately and when one runs out just switch over to the fresh one. Much safer !

Phil

ruralweb
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Re: solar/ battery charging.^

Post by ruralweb » Mon Feb 04, 2013 11:23 pm

That's me not explaining myself correctly as usual. As you say ill tape them together but use them separately which should with luck get almost 3 weeks of iPhone power. I've just bought an iPad mini to use as a GPS so next I need to see how long I can get that to work for. Just thinking about my old blackberry perl you could get a couple of months out of them.
Mal

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