Well firstly the specs of the Solar Cell
by
hal 9000
·
about 18 years, 10 months ago
In reply to Solar panel for running a notebook?
Say recharge not run and if you look at the specs of both items I very much doubt that the Solar Cell will provide enough voltage to actually charge the battery.
The Solar Cell produces 15.1 Volts DC MAX and the Compaq Battery is 14.4 VDC Battery so under ideal conditions without any protection circuitry the ability to charge the LT’s battery would be marginal and that is only with the standard battery not the large capacity one that is optional. The estimated recharge time from the mains is a little over 3 hours so with this Solar Cell you can at the very least triple that time again under ideal conditions as the Solar Cell doesn’t provide anywhere near the same amperage as the mains charger.
While it is one of the new generation Solar Cells these are not all that efficient and are at best only about 8% efficient compared to the older generation ridged cells which have a 22% efficiency rating. So you’ll need a much bigger area for the same power supplied from a conventional Solar Cell. Not to mention the price difference between the two.
Now as far as protection circutirty is concerned the above posting gives you the right idea but you also need a cut out so you will need to build some form of monitoring system into the circuit to cut off the Solar Cells power when the LT’s battery is fully charged so as not to damage it you can not rely on the built in protection as it is aimed for a much larger amperage and voltage so in all probability it will not cut off the power when the battery is fully charged and cook the battery slowly. The resulting fumes that are let off by the Battery could well destroy the LT all together as they are very acidic and consequently quite harmful to the LT’s internal components.
Personally I would buy a few spare batteries and then if you are going to be away from mains power for long periods you’ll need a higher Voltage Solar Cell and some very sophisticated protection circuitry that can charge the battery out of the LT and cut off when it becomes fully charged. I would recommend a 20 VDC Solar Cell for this and as high an amperage as you can get then you can build the protection and cut off circuit and connect it directly to the LT’S battery when it is out of the LT.
I would also only consider using the ridged Cells as they are far more robust and less susceptible to damage than the flexible ones are. Sure it is nice to be able to roll it up and pack it away but if you roll it too tightly or drop something onto the Solar Cell you can destroy it where as with the ridged ones you can drive a car over them without doing any damage.
I’ve used this type of thing in 3 rd World Countries where there is no reliable power supply and they are quite effective even though the roof of a car is used to mount the Solar Cells on and the batteries are charged inside the car while you are away and the car has to be left in the sun so no parking it under cover or the efficiency drops as low as 2% on a sunny day and nothing when there is no direct sun light.
It would work out much cheaper to buy a small petrol generator to recharge the LT and with what you save on the generator you could buy several spare batteries as currently here I can pick up a 750 VA generator for $199.00 AU compared to the $300.00 US price tag for the Solar Cell.
The generators are small enough to fit into the boot of a car and have the added advantage of not requiring any other modifications to recharge the LT as all of the recharging circuitry is already built in or provided by Compaq. With one of these it would even be possible to not only run the LT but be recharging it at the same time so you wouldn’t have the massive time delays involved in recharging the battery.
Just something to think about.
Col ]:)