Glowing Solar Balls

ChrisOlson · November 2012

Late last summer my wife bought 10 glowing solar balls that go on short stainless steel posts that stick in the ground. They have a glass ball on the top, there's a little solar panel that charges up a double A battery, and the battery powers a LED inside it when the sun goes down. She put them along the sidewalk that goes to the driveway, and was so proud that we got a lighted walkway at night. And they do actually give off enough light to light the walkway, and look kind of cool. We lived here for 8 years, totally pitch black at night except for what light comes from the stars or moon, and this was her contribution to having some outside lights at night.

Well, her glowing solar balls quit working in the last month. The amount of solar energy we get this time of year is just enough to charge them. So they come on real dim for about 15-20 minutes when the sun goes down, and then they go dark. She was so disappointed that her renewable energy sidewalk lighting system quit working that I finally had to take the batteries out of the things, bring them in and charge them up with a little double A battery charger for her.

After charging the batteries up they worked fine for two nights and now they're dead again.

The batteries in them say on them that they're 2000 mAh. The type of battery they have is NiMH, 1.2V. It can't take a lot of solar energy to charge those up, but we don't get a lot either. We got .8 kWh today from 3.5 kW of installed solar capacity, and 1.1 kWh yesterday. But it seems even at at those levels of solar insolation that the little solar panel her glowing solar balls got should be able charge up a 2000 mAh battery.

I don't think these batteries in these things hold their charge very good in cold weather, might be part of the problem. Is there a better type of rechargeable battery that might work in these things for cold weather? I checked the solar output today and my DVOM showed 1.98 volts coming from the little solar panel without a battery in the thing. So the solar panels are working - it''s just not charging much.
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Chris

BB. · November 2012

Re: Glowing Solar Balls

Over the years, I have seen most of these types of lamps using NiCad AA or AAA batteries. Probably 1/2 the storage capacity but very good for running "dead" (less chance of damage).

Also, longer cycle life and wider operating temperature range (Comparison of NiCd, NiMH, and Li-Ion Batteries pdf):

Operating Temperature
NiCad -22 to +140°F (-30 to +60°C)
NiMH -4 to +122°F (-20 to +50°C)
Li-Ion +14 to +122°F (-10 to +50°C)

Charging Temperature
NiCad +32 to 113°F (0 to +45°C)
NiMH +32 to +113°F (0 to +45°C)
Li-Ion +32 to +104°F (0 to +40°C)

-Bill

niel · November 2012

Re: Glowing Solar Balls

those things are cheap and you can't expect them to last as they don't make them to. high usage combined with low solar input is a recipe for failure in any book. it may be worthwhile to wire them if you like them that much. it would take a bit of ingenuity with the 12v pvs and higher 12v batteries that are common, but figure wiring 10 solar lights in series to reach the 12v battery voltage. i've never ventured this far with these things and i'm not sure how well this external powering of it would work out as they come on at different times. even the more expensive solar lights are lacking in reliability, but it may prove to be easier to provide external 12v power to these. i believe some of the pwm sunsavers are geared for lighting purposes so that might help with the timing aspect.

this may need to be a project both of you need to address rather than just her as there are reliability issues with them at the start. even i had to recharge my solar lights indoors to keep them going and it was a royal pain to do when everything is frozen over in snow up to the light and to access my battery on each light i needed a small phillips head screwdriver. a wired low voltage lighting arrangement is better and can be kept in electric from inside the house more reliably.

ChrisOlson · November 2012

Re: Glowing Solar Balls

It's interesting to see in Bill's information that the charging temperature is 32 or above. It's been more like 3 - 15 degrees here. So maybe they're not meant for winter, although it didn't say that on them. The ground is froze solid as cement so wiring them all in series is probably not an option right now. We DO like the lights. So I think the first thing I'll do is see if I can get some NiCad batteries and try those.

I think they don't require direct sunlight to charge up - they just work off ambient light. They have to because the solar cell is inside the glass ball. Being I get 1.98 volts from the solar panel in it, and that's considerably above 1.2 volts for the battery, I see no reason why they shouldn't be charging, other than it's too cold.

Thanks!
--
Chris

Dill · November 2012

Re: Glowing Solar Balls

I have a few of the small walkway lights except mine have the panel on top of the housing. This will be the 4th winter I've used them, they do get direct sunlight when it's sunny though. Still on the original batteries too. I bet they probably aren't getting enough current through the glass with how low the sun is up here these days?

ChrisOlson · November 2012

Re: Glowing Solar Balls

Dill - I tried to figure out a way to see if I could measure the charging rate but it's hard to do because as soon as the battery is installed it "clamps" the voltage down to the battery voltage, which is dead. But without a battery they put out good voltage. So I have to believe the power is there to charge them, but because the battery is cold it maybe isn't accepting much current?

The glass balls aren't clear - they're a like a crackle ball so they diffuse the light from the LED. I see no reason why, as long as there is light, that they shouldn't charge. Even in the shop, with the light from the shop lights, the little solar panels put out 1.70 - 1.75 volts. And with a fully charged battery (charged with a plug-in charger) they will run for two nights.

So I don't know for sure. My wife sure would be happy if I could get her lights working again. And there has to be a better way than swapping the batteries out every two days with fresh ones off a plug-in charger.
--
Chris

nvyseal · November 2012

Re: Glowing Solar Balls

Hi Chris,

You might try eneloop batteries http://www.microsoftstore.com/store/msstore/en_US/pd/productID.239373900?WT.mc_id=mercent&mr:trackingCode=58A719B2-EC65-E111-B2BE-001B21A69EB0&mr:referralID=NA&mr:adType=pla&mr:ad=15239889307&mr:keyword=&mr:match=&mr:filter=21844073347&origin=pla

I have solar walk lights also, popped these in, and they last me about 2 weeks until i need to recharge with the indoor charger during winter. summer i dont need to recharge at all. They stay on all night too.

ChrisOlson · November 2012

Re: Glowing Solar Balls

Guys - I think I may have discovered the problem! It's the light sensor. The lamps have a little white light sensor on the side of the housing below the glass ball. I put in a fresh set of batteries and took the lights out to put them on their posts and they came on - the LED is on. I looked at the four that are were laying on the ground yet and two were on and two were off.

The lamps have a switch on the bottom to change them from white light to alternating colors. When I put them on the posts I tend to put the switches on the side opposite the walkway because my fingers are touching the switch when I put it on the post, and that just seems "natural" so the switches are all in the same place.

Well, that positioning happens to point the light sensor towards the house and walkway where there is no snow so it evidently doesn't get enough light to turn it off. I turned the balls on the posts so the light sensor is pointing away from the house towards the snow on the ground and they turned off!

I think the light sensors are not picking up enough light when it's heavy overcast, pointing towards the bare walkway, so they have been leaving the LED's on during the day. Every single one will come on if I point the sensor towards the walkway, and turn off if I point the sensor towards the snow.
--
Chris

icarus · November 2012

Re: Glowing Solar Balls

We have some similar cheap solar lights that we use to mark dock edges, walking paths etc. We even have one into a hand drilled hole in a submerged rock 150 meters off shore as a marker light. I have of und that the batteries are terrible and they jut need to be replace.

The scarry aspect of these, is that they are sold by the millions, and because they are so cheap, people buy them, and when they fail,they toss them in the trash,, along with the toxics in the batteries. I am very diligent about taking them apart and recycling the batteries,but I bet there are millions in landfills around the world. NI CD LI. Etc,

Tony

westbranch · November 2012

Re: Glowing Solar Balls

you can use regular AA batteries, just don't recharge, last about a season

ChrisOlson · November 2012

Re: Glowing Solar Balls

westbranch wrote: »

you can use regular AA batteries, just don't recharge, last about a season

I thought about that. But the glass balls don't come off and there's no way to disable the little solar panel in there. I found the light sensors are VERY sensitive. All I have to do is walk by one and reduce the light to it with my shadow and it comes on.

I found some NiCad rechargeable AA batteries at the Dollar General store in town. It doesn't say how many mAh they are. I checked the voltage on them and they are 1.37 so I think they are fully charged out of the package. I will put those in after lunch, being careful to position the light sensors where they get good reflection off the snow, and see what happens. We actually have sunshine here today and our solar array is producing 52 amps with the bank absorbing at 62.0 volts! So I think the NiCad's should charge up thru the afternoon if they're not fully charged.

I am now convinced they were simply staying on during the day, so the batteries could never get charged up. And with the batteries mostly dead the LED is very dim so we didn't notice it.
--
Chris

westbranch · November 2012

Re: Glowing Solar Balls

Chris, we have averaged about 4 years out of the ones we have used.... so you probably hit on the problem. I have noticed on 2 that are > 10 years old that the sensor 'weakens' and they come on early in the evening, about 2 hrs before the rest...

ChrisOlson · November 2012

Re: Glowing Solar Balls

Indeed, I was surprised to see them that sensitive. Now that I know it I'll watch them closer to make sure they're turning off when the sun comes up on cloudy days.

For off-grid outside lighting at night, they are very nice. It's really surprising how much light they give off when there is no other lights. This is the first ones we've ever had. They don't look cheap like you guys are talking about. They are all stainless steel and appear to be completely weatherproof - even the battery compartments are totally sealed from the weather. It says Geo-Technik Solar Systems GmbH Germany on them. My wife is European (Sweden) so she looks for this for when she buys things and I think she said she paid around $200 for them.

Thanks for all the info (especially on those rechargeable batteries), and hopefully I have found a way to keep them working in the winter.
--
Chris

BB. · November 2012

Re: Glowing Solar Balls

Alkaline batteries are sort of rechargeable if recharged before they go "dead" (you can buy rechargeable alkaline batteries and chargers--But they really were not worth the trouble (shallow discharging and not that long of battery life, plus not very good surge current like NiCad and NiMH, etc.).

If you have a couple, why not try them and see what happens (solar panels don't have enough current to "blow up" the alkaline cells--just pull them out if they don't work/go dead so they don't leak).

-Bill

ChrisOlson · November 2012

Re: Glowing Solar Balls

Bill - the only alkaline batteries I have are not rechargeable and I keep a couple spares for the temp sensor for our home weather station because it uses a set of batteries about once a month in the winter. Curiously, the temp (thermo-hydgo) sensor for our home weather station has a solar panel that provides power to it. It says to NOT use rechargeable batteries in it - only alkaline or LiIon type. The batteries in that sensor will last all year, except for the period from Nov to Feb 1 when we get very little solar insolation here.

I've never been able to determine whether the solar panel for that temp sensor actually charges the non-rechargeable batteries in it during the day, or if it just helps offset the amount of power that has to come from the batteries to operate the sensor. The anemometer head for the weather station is at 74 feet off the ground on one of the turbine towers and that also has a solar panel on it with alkaline batteries. I have never replaced the batteries that, and they're still fine after 2 years. The weather station shows the condition of the batteries in the sensors and the two year old alkalines in the anemometer head it still shows at "100%"

I did pick up some NiCad's for the lights. A few days will tell how well they work. I have to believe those LED's in the solar ball lights are very, very low draw things.
--
Chris

BB. · November 2012

Re: Glowing Solar Balls

Just use the regular alkalines--Two cells and see what happens.

Energizer makes some AA 1.5 volt Lithium primary/non-rechargeable batteries (PDF) that are supposed to be good to -40F/C... Used by snow campers for lights, GPS, etc... They also (at times) make AAA versions too (a few years ago, the availability of AAA were spotty).

-Bill

niel · November 2012

Re: Glowing Solar Balls

i would use caution in recharging regular alkalines. they can take a light charge, but won't take to the standard 5% or 10% charge rates well without heating up. i have fed about 5-10ma to an alkaline for awhile without repercussions. if attempting to recharge them then i would never leave these batteries unsupervised even with a low level charge.

BB. · November 2012

Re: Glowing Solar Balls

I think the solar yard lights only generate a few 0.010's of amps (10 milliamp) or so of current... The cells will not overcharge a plain Alkaline battery to destruction... But they could leak if left in and they are not functional (some sort of dead).

They did, for a short time, sell chargers for plain alkaline batteries--Those could be more of a problem.

-Bill

ChrisOlson · November 2012

Re: Glowing Solar Balls

niel wrote: »

i would use caution in recharging regular alkalines. they can take a light charge, but won't take to the standard 5% or 10% charge rates well without heating up. i have fed about 5-10ma to an alkaline for awhile without repercussions. if attempting to recharge them then i would never leave these batteries unsupervised even with a low level charge.

Yeah. I don't want to have one blow up or something and wreck one of my wife's lights. I'll try the NiCad's I got here first and see how they fare.

Those little solar panels must be able to put out pretty good power for their size. It takes two days to completely kill a 2000 mAh battery and in good sunlight they seem to keep them charged up. Leaving me to believe they must make at least 500 mAh in a day with 10 hours of sunlight. Or possibly a charge rate of 50 mA?

Thanks!
--
Chris

unicornio · November 2012

Re: Glowing Solar Balls

http://en.wikipedia.org/wiki/Rechargeable_alkaline_battery

There is a type of rechargeable batteries that are called "rechargeable alkaline" but have nothing to do with ordinary alkaline batteries that you Never attempt to recharge ...;-)

These batteries are suitable for devices that have very low consumption, because regular rechargeable batteries (Ni-Cd, Ni-MH) have a rate of "self-discharge" that does not support its use in devices of very low energy consumption, since their current of self-discharge are higher than the device consumption itself ...

for weather station with a little solar panel is necessary to use this type of battery and in my experience with my PCE-FWS ( taller ecologico "los unicornios" weather station )and can last many years because of its low consumption makes the that the small panel is enough to keep the battery in a healthy state ...

I too use this type of rechargeable batteries for my low-power devices or I use very little beause before, with the other rechargeable batteries, when I wanted to use had I find always discharged (and maybe broken) batteries ...

These batteries come fully pre-charged from factory, and its charge lasts years (still within the blister) so also are great for storing for a long time for emergency situation purpouses ...have been called "rechargeable alkalines" precisely for this feature ... are a little more expensive than Ni-mh and ni-cd, and have lower capacity, but for these purposes are more durable than the otherstypes with more higher capacity, so the pricely it is worth, and too, have a good number of life span and charge cycles ...

can be fully charged with any good charger like these for Ni-MH or Ni-Cd batteries ... we use only rechargeable batteries, and use this high quality, testing / charging / maintained charger, "practically" for all kind of rechargeable battery...
Attachment not found.
http://www.tantronics.co.uk/acatalog/Ansmann_Energy_16.html

hope this help! ...;-)

inetdog · November 2012

Re: Glowing Solar Balls

unicornio wrote: »

http://en.wikipedia.org/wiki/Rechargeable_alkaline_battery

There is a type of rechargeable batteries that are called "rechargeable alkaline" but have nothing to do with ordinary alkaline batteries that you Never attempt to recharge ...;-)

hope this help! ...;-)

For whatever reason, the rechargeable alkalines are not very common in the US anymore. Before NiMh was introduced they were seen more.
I believe that these rechargeable alkalines share a characteristic with Li chemistry in that once you go below a certain DOD they are no longer rechargeable. Just something to keep in mind. The extra capacity is available as a "reserve" when they cannot be recharged in time.

unicornio · November 2012

Re: Glowing Solar Balls

inetdog wrote: »

For whatever reason, the rechargeable alkalines are not very common in the US anymore. Before NiMh was introduced they were seen more.
I believe that these rechargeable alkalines share a characteristic with Li chemistry in that once you go below a certain DOD they are no longer rechargeable. Just something to keep in mind. The extra capacity is available as a "reserve" when they cannot be recharged in time.

from wikipedia:

8<

Chemical composition
Rechargeable alkaline batteries are a development of primary alkaline batteries. They resist leakage that a recharge would cause, so they can be safely recharged many times.
Some other types of rechargeable cells contain mercury or cadmium and thus are a serious environment hazard unless special care is taken for their disposal. As of August 2007, a number of companies make batteries that are free from these heavy metals. According to the websites of EnviroCell[2] and PureEnergy and according to old Rayovac packaging, these manufacturers' rechargeable alkaline batteries have no mercury or cadmium.

8<

so I think that are a development from the normal akaline that are not rechargeable, I think that share much of this technology...but I'm not quite sure even what it read on wikipedia, I am very skeptical! ... hehehe
but I discharge them very deep, I recharge and nothing seems to happen ...it work fine...

ChrisOlson · November 2012

Re: Glowing Solar Balls

The NiCad batteries that I got at the Dollar General store today for our lights are MoonRays brand and it said on the package they are for solar lights.
--
Chris

BB. · November 2012

Re: Glowing Solar Balls

NiCad AA batteries usually run around 900 mAH.

-Bill

niel · November 2012

Re: Glowing Solar Balls

it's hard to second guess what he is looking at in capacity as i've seen some of those nicds for solar lights down pretty low in capacity. around 450ma comes to mind for one i had.

having 900ma may not work out either if there's insufficient charge coming from the solar panel.

ChrisOlson · November 2012

Re: Glowing Solar Balls

I got three four-packs of them and didn't see it at first - but after I put my reading glasses on to see it, it says on the fine print on them that they are 600 mAh.

My wife saved the instructions for the lights. It says right in there (if I would've cared to read it before this) to use 600 mAh Ni-Cd batteries in them. They did not come with batteries and she bought 2500 mAh NiMH Energizers for them. It also says do not put bigger batteries than 600 mAh in the lights because it will not fully charge the battery and will not increase the running time of the light.

There's a reason they send instructions in the package I guess. But who reads them until something doesn't work?

--
Chris

2twisty · November 2012

Re: Glowing Solar Balls

Lol. This seems to be an awful lot of trouble. Just take a flashlight!

niel · November 2012

Re: Glowing Solar Balls

your answer seems simple enough, but doesn't wash in reality for it's difficult to hold a flashlight when carrying lots of groceries for example. ideally some low level lighting would probably due just fine, but they have to be more reliable. if they had bigger cells in the lights and better capacity in the batteries then maybe they wouldn't have such a poor track record and would be more functional. maybe even a better charge circuit too as i'm not real sure how they went about it even though i remember seeing a schematic long ago. i just didn't pay that much attention to it as it hardly seemed worth my time. another fine example of manufacturers cutting corners i suppose. heck i'm still waiting for them to make an electric weed whacker that will go more than a season or 2.

Ralph Day · November 2012

Re: Glowing Solar Balls

Hey Neil, electric weed whackers last forever. If you swing them hard enough from side to side they act like our grandparents scythes would...hence the longevity. That's if you haven't done the olympic hammer toss with it when the battery quits after 5 minutes:p. My method doesn't make for a very even cut close to fences, houses, trees...actually anywhere.

Ralph

westbranch · November 2012

Re: Glowing Solar Balls

I had a grid powered WW and found it scary in long grass (> 1 foot tall) Never knew what would come flying out at you...

Only thing that seemed to stop it was quack grass or alfalfa.

ChrisOlson · November 2012

Re: Glowing Solar Balls

We have a 12V electric Toro weed whacker and love it. The SLA battery in it is two years old and it still runs about 45 minutes on a full charge. Most people leave the chargers on after the light turns green all thru the season, then forget to maintenance charge the battery once a month in the winter, and they go bad. If you take care of it they last fine. Those little SLA batteries in those things won't handle being held at a constant 14.4 volts all the time, nor is it good for them to be allowed to self-discharge over the winter without being maintained.

--
Chris

Glowing Solar Balls

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