Power Tanks in Aldi

Looks the same as this one on the TS site (€69 plus shipping)

www.telescope-service.com/mount_accessor...ries_start.html#akku

Loos like a good deal

Lads,
I've been doing abit of research on batteries to run the Obsession and have found a few points that might be useful here.
I suspect that these packs use a standard sealed SLI (starter,lighter,ignition) lead acid battery, if so, I wouldn't use this battery pack if your system draws a fair amount of power, like say 2 or 3 amps, in this case you might be using a hefty mount and dew heaters.

These SLI lead acid batteries they are not designed for prolonged use but are used for short interval use.

If you discharge more then 20% of its capacity, you can permanently damage the battery, if you go alot further you will definitely damage it, do this a number of times times and what you'll find is that the time it runs your scope in the field will become shorter and shorter and a time will come when it might not work at all.
In this case you'll need to replace the battery in the pack.

I used to go through a car battery every 8 months or so when I was using it to run my LX200, I couldn't figure out why, but now I know that I was draining them way beyond their ability to come back to life after a recharge attempt.
If you have a low power system like say an ETX, then get your self a cheap voltmeter and make sure that your SLI battery never runs below 12.5 volts (a 12volt battery is actually 12.65-12.7 volts), when it gets to that point turn the scope off.

For a higher power system, what you want is a reserve capacity battery such as a deep cycle battery a leisure battery or a marine battery (preference in that order). Its preferable to get one that isn't sealed so you can top up the electrolyte when needed. These batteries can discharge 70% and be recharged with no ill side effects.

One rule with all batteries is to recharge them ASAP after use, do not leave them lying around discharged.!!

I hope this helps some of you with out with battery concerns.

These SLI lead acid batteries they are not designed for prolonged use but are used for short interval use.

That's the catch, as it is a starter pack for your car with the ability to run tools for a breakdown assist. However, I have seen some folks get about 3 hours use from it running a camera, dew heater, CG10 mount and scope, and a laptop. Now, that's good going!

mine was 30 quid in maplin just before xmas. could they have overcharged you Darragh?

Nope, it said €66 on the display rack and they are marked as £40 sterling on their website.
So they must have gone up in price, or you were very lucky

Darragh

Hi Darragh,

I got one of them myself for €30. I think they were on special offer at the time. I was planning to run my laptop off it but reading Dave's post I'm wondering if that will damage it.

Michael.

Hi Darragh,

I got one of them myself for €30. I think they were on special offer at the time. I was planning to run my laptop off it but reading Dave's post I'm wondering if that will damage it.

Michael.

Michael,

According to some of the electronic engineers I work with, for digital electronics like laptops, you need a very clean filtered source to run them.
A unit like this will probably not have the required filters, but then again I have used an inverter to power a laptop off a car cigarette plug and it charged up the laptop battery.

Darragh

Side stepping slightly off topic for a moment, you can get rehcrageable batteries specifically for the laptop (16 and 19V). I got one for my own laptop (Toshiba) and it gives me an axtra 1.5 to 2.5 hours (depending on power demands) along with whatever life is in the laptop (about 1.5 hours).


Lithium-Polymer battery .

Key Features:
Laptop Compatibility
The battery comes with 12 mounting adapters that will fit notebooks from many popular manufacturers. Adapters are included to fit notebooks from Dell, Canon, IBM, Compaq, Acer, Gateway, NEC, Hitachi, Toshiba, Sharp, BENQ, Clivo, Winbook, ACOM, ACT, AMI and Apple.

Fast Charging
The battery can be fully charged in as little as 5 hours. This allows you to easily charge it to full capacity overnight so that it is ready to go for your workday. The battery has no memory effect, so you can charge it at any time.

LED Indicator
The battery features an LED readout to give you a good idea of the amount of power left in the battery at all times. This lets you know when it is time to recharge.

Another alternative is to run your machine from your car cigarette lighter directly, but you're limited by cable length.

Just in case anyone is looking for an alternative.

Seanie.