Solar battery chargers for M8/M9?

[!Nomad64]

Advertisement (gone after registration)

Hello everyone.

I'm stuck into searching a solar battery charger to recharge M8 battery when electricity is not at hand.

I found this one, made by Silva:

 

http://www.silva.se/en/Products/Outdoor-Instruments/Portable-Power/?productId={A5BF6140-CFAE-49A0-83AE-3C156B2E8F33}

 

whose max output is 13.6V, 350mA (4.75 Watts).

 

M8 standard charger accepts 12-24V - 1.1A and throws into the battery 3.75V - 750mA.

 

So, whilst voltage shouldn't be an issue I'm somewhat confused about Amperage, which is safe, but pretty low.

I believe that this would ultimately turn into simply longer recharging time, but I also fear that the juice provided couldn't be enough to fully recharge the batteries.

 

Any clue anybody?

 

Thanks in advance,

 

Bruno

[jank]

Bruno, the Solar battery charger is not adequately described.

If it is just a plain solar panel capable delivering those 13V/350 mA at one full sun, it might work on bright days.

When one considers M8 charger efficiency to be about 60% it is barely adequate.

Assuming there is no electronics ( a switcher) , It could deliver up to 20V with no load e.g. when M8 charger already fully charged the battery.

.The question is what happens on cloudy day when the output voltage drops to 8 or 10V under the load?Would M8 charger behave well?

Will M8 charger shut down? How good is the design?

Most accessories for use in car are designed to operate down to 8V or less.

 

Really safe way would be to use Silva charger to maintain a small ,few AH 12V battery fully charged and in turn use it to charge M8 battery.

Then you could recharge M8 any time.

Added weight might present a problem.

Jan

[!Nomad64]

Thank you Jan, you raised points I didn't even think of.

 

Thanks again,

 

Bruno

[bedaberger]

I did'nt try, but I think this one is good:

Solio Portable Solar Chargers | Universal Solar Charger

 

It has a buffer battery, you can then charge your camera battery at night, or even when there is low light outside.

You can get constantly 12V from it.

[!Nomad64]

bedaberger, thank you for your input, I'll check this one too.

 

Best regards,

Bruno

[vla]

i took the solio to brazil last summer. one day i left it on the terrace for an entire day and it got wet due to some rainfall (nothing dramatic, just your usual tropical afternoon shower). the charger was dead afterwards.

i found this quite disappointing and would clearly expect a solar charger to be rain resistant.

markus

[!Nomad64]

Advertisement (gone after registration)

I did'nt try, but I think this one is good:

Solio Portable Solar Chargers | Universal Solar Charger

 

It has a buffer battery, you can then charge your camera battery at night, or even when there is low light outside.

You can get constantly 12V from it.

 

Checked the specs of the Mag, apparently the most powerful: Solar panel max output 0.85 watts (5.5 V 150mA). Rechargeable 3.7V 1800mAh Lithium Ion battery.

It's not possible to plug it into the M8 standard charger as it lacks the necessary voltage (and the dedicated tip). The buffer battery has the same voltage as the M8's, so I guess that with some DIY adapter it might be possible to connect and partially recharge the M8 battery.

That's not exactly what I'm into, but thanks anyway for the input.

 

Bruno