[Power] [support-gang] External "power bank" for XO's ?

[Nicholas]

Hello,

Maybe this might be helpful (or not).
There is a commercial product called the Aili 119 for laptops and 5v needs. It is available from Aliexpress among other places.
It is a portable 18650 powerbank but unlike the others it has 3S2P making it a 6Ah 12v battery bank (with 6x 3000mAh cells). It can be purchased with interchangeable heads like the 12v (car) laptop power supplies you can buy (a chopped OLPC power lead and be wired into a standard barrel connector).

I've been using 2 extensively over 3 months. They are reliable and have cell balancing tech in there by the looks (and claims). The enclosures are a bit flimsily built plastic but apart from that they are good. They will go down to under 5v to over 21v  (buck and boost inside).

They have input circuitry which allows them to be charged by solar, limiting the input current to 1.5A approx. So a 25w panel charges the battery bank efficiently. A car on an alternator can also charge the bank. There is a usb output and it will charge both major charging types (Android/Apple) at a reasonable clip.

For the price (around $20 + cell costs), as a solar charging system that will in turn provide power for most needed DC appliances up to 75w they are a good investment. If you have access to 6 18650 cell laptop battery packs that are in a healthy or new state these can provide the juice. I've found the little welds to the tabs can be pulled off (with care). A job for someone with some electronics experience and/or practical nouse.

Best regards,
Nicholas

----- Original message -----
> Nathan
> 
> I have tried to standardise on 12V powered gear as it really makes it
> simple for field work.
> SLA batteries and chargers are pretty cheap and readily available.
> 
> Like you, I also found trying to work from 5V battery packs with step up
> to 12V to be problematic.
> 
> Thanks for the link, that is a nice board for a solar powered system. It
> would be good to find one that does the load cut off at low battery as
> well.
> 
> The unusual sized power connector on the XO is a bit of a problem to find
> replacement parts, but they are around.
> It is the small centre conductor version (? 1.7mm) that seems hard to
> find.
> 
> I have also found that with age the connectors on the chargers don't make
> good contact as the V shaped centre contact spreads apart. But they can
> be pushed/bent back into the middle of the connector to extend their
> life.
> 
> On Tue, Jan 26, 2016 at 12:01 PM, <nathanr333 at charter.net> wrote:
> 
> > Terry,
> > 
> > Again, thanks for suggestions.
> > 
> > I do have the 3 A version (slightly lower cost) of this board.   It also
> > permits charger input instead of solar.     OLPC chargers   ( 12 V and
> > 13.5 V) would not work since module is only voltage bucking device and
> > lead/acid 12 V batteries are about 14.3 V at full charge.   (In my
> > solar application, this board feeds a Li battery charging/protection
> > board for 14 V   output).
> > 
> > I have used a 5 V   to 12 V boost board enough to know that XO-1
> > requires almost 1 amp to start and about 3/4 amp to run. The 5 V had
> > to supply the board at least 2.5 amp at start.   This beyond the output
> > of maximum of 2.1 amp of most 5   V "power banks".
> > 
> > A hard part is getting   the XO compatible connectors needed.   :(
> > 
> > 
> > http://www.ebay.com/itm/BQ24650-5A-MPPT-Solar-Panel-Lithium-Lead-acid-Battery-Charging-Controller-Board-/171753976645?hash=item27fd55b345:g:H9QAAOSwMmBVuyYI
> > 
> > Nathan
> > 
> > -----------------------------------------
> > From: "T Gillett"
> > To: "Community Support Volunteers -- who help respond to help AT
> > laptop.org"
> > Cc:
> > Sent: Tue, 26 Jan 2016 08:47:12 +1000
> > Subject: Re: [support-gang] External "power bank" for XO's ?
> > 
> > Ahhh   I see we have additional requirements to meet...
> > 
> > Travel and shipping requirements for small, non-spillable batteries
> > (<100 Watt Hours) are not that onerous.
> > If they are properly installed within a piece of equipment that is
> > prevented from being accidentally switched on, then you have met the
> > rules and won't attract undue attention.
> > 
> > Lithium based batteries do require additional care and can attract
> > extra attention however, simply due to their chemistry and the
> > possibility of burning.
> > 
> > I imagine you don't want to modify the XO so that it retains its
> > qualification for travel and shipping. The goal is just to have an
> > additional source of power plugged in via the charging socket -
> > correct?
> > 
> > In this case you need a nominal 12V supply for the XO.
> > 
> > A 12V battery mounted in a suitable enclosure with a switched, fused
> > and pluggable output cable, combined with a matching plug pack charger
> > would fit the bill. Such a thing is fairly easy to assemble, and you
> > can probably do so for under $30 all up with a common 4AH SLA battery
> > and a 1.25A charger.   Of course you can use other battery types as
> > well. There are also commercial products like this, but perhaps not in
> > as small a size as you are looking for.
> > 
> > But if you must re-use the original XO charger, then it is going to be
> > a little more complicated because you can't directly charge a 12V
> > battery from a 12V supply. If you include a step up DC-DC converter
> > with adjustable voltage and current then you can use that as a simple
> > charger within the enclosure. Or use a more elaborate charge circuit.
> > 
> > 
> > 1.25 A SLA Charger $8
> > 
> > http://www.ebay.com.au/itm/12V-Volt-1250mA-Sealed-Lead-Acid-Rechargeable-Battery-Charger-SLA-Computer-AU-/190615897043
> > 4AH SLA Battery   $14
> > 
> > http://www.ebay.com/itm/Casil-Genuine-CA1240-12V-4Ah-SLA-Alarm-Battery-Brand-New-2016-/291575671757
> > DC-DC Converter $3
> > 
> > http://www.ebay.com.au/itm/Boost-Buck-Voltage-LM2577S-LM2596S-DC-DC-Step-Up-Down-Power-Converter-Module-/191149033807
> > 
> > 
> > On Tue, Jan 26, 2016 at 4:42 AM, <nathanr333 at charter.net> wrote:
> > 
> > > Terry,
> > > 
> > > Thanks for suggestion.
> > > 
> > > Since XO LiFePo4 batteries are no longer manufactured, I am looking
> > > for a means of battery power when current batteries reach short run
> > > times near end of usefull life.   The targeted features sought are:
> > > fit in a small brief bag with XO, can be carried on airplane, can be
> > > mailed   with an XO, cost similar to XO battery and use XO   charger. 
> > > The devices mentioned met some of the features:     about the size of
> > > my hand, similar or greater run time, cost equal or slightly higher
> > > than XO battery, certified for transport and mailing, and in some
> > > cases could use XO charger.
> > > 
> > > They do   cost 2X of a sealed (gel) lead/acid battery with charger.
> > > 
> > > Posted earlier that I have been able to rebuild an XO battery using
> > > 4 of 18650 cells and a slight modification of the battery case.     
> > > However, these would not be qualified (certified) for transport or
> > > mailing.
> > > 
> > > Hence, looking around for what might be available and continue to be
> > > available.
> > > 
> > > Nathan
> > > 
> > 
> > 
> > _______________________________________________
> > support-gang mailing list
> > support-gang at lists.laptop.org
> > http://lists.laptop.org/listinfo/support-gang
> > 
> >