Several questions for Parallax
Buck Rogers
Posts: 2,161
Hello!
First of all is Parallax coming to this year's Maker Faire?
Second of all for this battery box, https://www.parallax.com/product/28989
why was this battery pair https://parallax.com/product/28987 chosen.
It turns out Radio Shack (Yes erco Radio Shack. I think they started selling them shortly after surviving their bankruptcy scare and failure.) is selling them, and all I could find was a pair of the 2000 MaH style. They are supposed to be these http://radioshack.com/digital-energy-3-7v-2000mah-18650-li-ion-flattop-w-pcb/2302471.html
and a pair with the button nose that's similar to the pair Parallax offers. (Except in capacity.)
I was thinking of using this guy https://parallax.com/product/28988 instead but I'm not convinced because the text about it is the same as the first one. The second one does not include charging circuity.
First of all is Parallax coming to this year's Maker Faire?
Second of all for this battery box, https://www.parallax.com/product/28989
why was this battery pair https://parallax.com/product/28987 chosen.
It turns out Radio Shack (Yes erco Radio Shack. I think they started selling them shortly after surviving their bankruptcy scare and failure.) is selling them, and all I could find was a pair of the 2000 MaH style. They are supposed to be these http://radioshack.com/digital-energy-3-7v-2000mah-18650-li-ion-flattop-w-pcb/2302471.html
and a pair with the button nose that's similar to the pair Parallax offers. (Except in capacity.)
I was thinking of using this guy https://parallax.com/product/28988 instead but I'm not convinced because the text about it is the same as the first one. The second one does not include charging circuity.
Comments
One is small enough to fix under a BOE-Bot or an Activity Bot. The larger one is the same size as a BOE.
The larger board has a couple extra connectors.
Either board can be used with just about any 18650 Li-Ion cell. The cells with extra protection tend to be a bit longer and are harder to install and remove from the charger/carrier.
Anything with 'Fire' in the name and you're lucky if you get 60-70% of the rated capacity, and a lot of those are actually just relabeled laptop battery back units with a new shrink-wrapped label.
Parallax needs to dump those batteries and that pic.
Compare:
http://www.ebay.com/sch/i.html?_odkw=ultra-fire&_osacat=0&_from=R40&_trksid=m570.l1313&_nkw=ultra-fire+lithium&_sacat=0
with the real-deal units, and note even here they are still at about 2600 mah max:
http://www.powerstream.com/18650-high-discharge-rate.htm
So you're saying Duane that either of the two 18650 Li-Ion cells (one pair from yesterday, and one from today with their one charger. Yesterdays needed to be swapped because of a quality control foul up.) will work in that box, and that the fact that the originals were 2600 MAh versus the 2000 MAh doesn't matter?
And I did hope that erco would comment first, too bad, Duane you're one who one the prize, I do hope your ready for six months on everyone's favorite desert planet.
Sadly I gave up on that site years ago when I found it to be nearly impossible to use. Its gotten worse it seems to me.
Interesting. The ones from RS it seems are indeed extra protected.
Where is the charge circuit for the smaller battery box?
I've flagged this topic to the product manager at Parallax.
I'd agree with @koehler about the branding issue, and my understanding is that #28989 does ship with the Tenergy cells #28987. (A recent delivery of said part included Tenergy!)
You can usually feel a difference in these batteries when you hold them. In preparing the new Parallax Badge recently we had similar experiences with some "low cost" batteries marked 2000mAh and some quality ones marked "700mAh". The 700mAh would be 3x the weight, and last twice as long!!
The metric for determining the stated capacity must be very different across manufacturers (or at least across marketing departments
Well since I started it, then "Thank you!". It seems I'm going to need to buy a pair from Parallax, and probably the smaller box.
My other problem is sorting out why there are no consistencies regarding the making of these batteries. Consider this, the ones that Parallax sells, the Tenergy ones, are a few fractions of an inch smaller then the ones that I bought which started this discussion.
Obviously when both of the battery boxes were designed, they were designed with the Tenergy ones as the standard.
Okay Duane you're going sharing this trip to that particular desert planet. How's it feel to be winners of an all expenses paid trip for six months to a very famous desert planet?
According to the product pages, the #28989 includes a set of batteries but the #28988 product pages states the batteries are not included. I'm pretty sure this is why the two products are priced differently.
MattG shared his experience designing the first charge board (the larger one) with the forum. The board was designed before the batteries were chosen. The first batteries sold by Parallax were the greenish "Ultrafire" cells seen in the product photos. These turned out not to work great with the charger because the batteries had their own protection circuit which didn't play nicely with the charger's circuit. They still worked but every so often a customer (myself included) would have to remove a cell and do something (which I no longer recall) to get the cell to again accept a charge.
Hopefully the Tenergy cells are better behaved.
I don't own a small board but the charge circuit must be on the bottom of the board.
Once the cost of the batteries are included the two boards end up costing the same.
The small board has the advantage of being able to fit under a BOE-Bot chassis but the larger board has a few extra connectors which could be useful.
The decision of which board to get will depend on how it will be used.
The Ultrafire cells are very hard to remove from the charger. These boards aren't really intended to be used as chargers per se but they're power packs which can be charged in place. The only time batteries are removed are when they need to be replaced.
If you want to use these as battery chargers then you should make some sort of addition to make it easier to remove the cells. A thin but strong ribbon may work. Don't dig the cells out with a screwdriver. A screwdriver could easily damage the cells (don't ask how I know).
Right now I'm pondering an interesting one, since the 14500 style approximates a AA size I'm leaning towards fabricating one of my own using two of those, and one of the famous battery holders from the same shop who sells them.
Now if a version is available in say (approximately) AAA size then I already have the holder for that one.
Some state the capacity their batteries can actually deliver, having no doubt measured it.
Others state the capacity the customer wants to buy. No doubt after having measured that.
Someone out there has earned the rubber foul award.
The one completely absurd thing going through my mind is one of, how do these batteries relate to the ones used in our laptops and cells and even other things that use them. (Including Parallax branded gear.)
The ones that Sparkfun sells do not have internal protection according to their website, either from themselves or from customer comments.
And didn't erco himself post that there's a holder available for printing via 3D printing processes?
There are AAA versions....
Search for Li-Ion 10440 3.7V
If hooking up to a charger intended for 14500 or 18650 series, remember to make sure the charge rate is not too high! Typically the 10440 want a maximum charge current of 250-300mA; much less than those larger mentioned batteries. The battery datasheet will confirm.
The same rules regarding battery length apply for all these cells. If they have the internal PCB, then the length is about 2 or 3mm longer. With those batteries with pcb, you can often see a cable on the side of the cell, running from gnd to positive terminal- of course that will be under the battery wrapping, so you actually see a thin lump running up the length of the battery
The battery with pcb will also often have a shorter (almost flat) positive terminal, to try keep them compatible with the appropriate series holder.
Regarding holders... you just need to get the battery measured, then check the holder datasheets before ordering. I've seen so many variants on AA holder lengths. Of those I found for the badge, the ones with big springs at one end seemed to take the largest range of battery sizes.
Makes sense. I was actually basing the majority of my references for battery designs to what's available from three places, Radio Shack now, Micro Center still, and Sparkfun, also from the NYU computer store's parts drawers.
So far RS is busy updating their inventory, and new stuff is arriving soon. What is decidedly interesting is that they do sell a charger which is capable of handling the majority of these gizmos.
Glad someone is listening!
There is no 'metric'.
This is simply common Chinese manf. PR.
From the people I've known who've actually been to China, and are involved in Manf/Prod, there is very little enforcement of anything we in the West are used to vis a vis profuct guarantees.
There is no down-side to out and out lying when it comes to product features.
When a brand finally becomes known for failing to live up to its product statements, its often easier to just close that brand down and start a new one under a different name. Only cost is some paperwork and new labeling.
@koehler... please consider removing or moving elsewhere the last 3 lines of your post as they are not within the realms of this thread or forum intent.
Thank you !
Those lines are not appropriate. I remember one list I belong to, one subscriber was asked to trim his signature in that it was about six or seven lines in length and he kept posting relevant one line answers, and those signature lines were not.....
Post edited to keep on topic.
More about the RS vended batteries. It seems that the original store's staff person, (but not the original seller) is indeed aware of this inconsistency. He's also aware that the company forgot one big detail, that of selling holders to accommodate the pair that I'm originally interested in.
Also the numbers that correspond to AA sizing aren't available from them. Probably from a different vendor in the City....
And I'm late to yet another party!
But can you offer any insight into the mess? I recall a discussion when I mentioned that the same style as this whole business is about, was from a Texas based shop (still are) you described a 3D printable box for the individual battery.
Don't think it was me. I do use a lot of 14500 batteries, but I use standard AA battery boxes.
Fine.
(Nice. Where did you get it from?)
It happens that RS does sell that size, some with an attached charger, and they are up to their ears in AA boxes.
Well one of you did, but the heck of it is that the newish search engine for forum doesn't like the way I type.
I still haven't confirmed when RS did start selling that series of batteries, both the size you mentioned and the ones that I did. And they agree that the missing link is a battery box for the 18650 Li-Ion ones. I have since decided that I'll probably very definitely soon buy a pair of replacements from Parallax, and will indeed fabricate a pack using the 14500s that RS sells, using two of their single AA boxes.
The four 18650 Li-Ion ones I bought (two with charger) will be applied to something other then Parallax work, unless I can track down a box for them.
Two of them are wearing flat heads, but they don't fit properly inside the box that I described above, that's the style who can go underneath the BOE board.
http://www.ebay.com/sch/i.html?_odkw=18500+battery+holder&_osacat=0&_from=R40&_trksid=p2045573.m570.l1313.TR0.TRC0.H0.X18500+battery+clip.TRS0&_nkw=18500+battery+clip&_sacat=0
Its a thought. Based on our earlier (in this thread) discussions, I found on Thingiverse several examples of how to print out via a Makerbot a battery box for these batteries.
Now remember I was convinced that you, yourself, erco did bring this idea up earlier. I'm still working on it....
Now I'm looking to use one of those batteries to run a QS (QuickStart) project.
The lion packs were originally designed with the flat top Tenergy cells as standard equipment. Both versions of the lion boards have the same exact charging circuitry, but they do differ in their output terminal arrangements, which makes the larger version more versatile for creating variations on the application at hand...an example would be that the larger board is crazy-easy to turn into an un-interruptable power supply as described in its documentation.
We've always been at the mercy of the lion cell market (18650 specifically) due to several factors. One of the biggest factors early-on was when we spec'd the Tenergy device as our defacto standard.
About 6 months after that spec, Testla Motors bought every Tenergy 18650 cell that the battery company could produce. Every one. (Their electric car - at that time - was powered by six thousand eight hundred 18650 cells...in each car).
So, because of lack of product source, we had to find alternatives - some comparable in specs, others not so much. Since we don't actually make the cells we're at the mercy of the cell markets.
Now that Testla is going to be making their own cells, that may ease the market crunch...only speculation.
Add to this that the charger chips have been discontinued for a couple of years now, it will require a re-design at some point if demand for the lion boards continues.
I could ramble more, but what else specifically would you like to know more about from our viewpoint?
-MattG
That was really important in applications that would require the boards to be upside down - like the Boe-Bot application.
and to be clear...both charging circuits are exactly the same - same components, same temp sensors, same current protection, etc. The only difference is the form-factor (the 3x4 stacks well with our other 3x4 boards) and of course the Boe-Bot version is sized/engineered to fit specifically that. (It only lacks the versatility of output options, that the 3x4 has)
-MattG
Actually Matt you've in both posts you've summarized everything perfectly.
However it now happens that those amphibians at RS sell batteries with that number on them. Two are indeed flatheaded, and two are wearing button noses.
And neither of them would be good matches for the style that was chosen for them from the catalog you used Matt.
Well anyway time continues to move in circles. I found this site, BatterySpace.com http://www.batteryspace.com .
Basically they sell scads of them from their location somewhere in the LA County area. Normally I'd find that one funny, but not now. They do sell holders for the size we're concerned with. Also batteries of that size.
To be honest I'm right now stepping my way through an idea. Naturally I'm buying the replacements for the rig we are discussing directly from Parallax. (Or from any US dealer who's close by.)
But for the ones I have, it'll probably battery holders from them.
Strangely enough RS does sell the 14500 style, with charger, naturally. Also one number, the 16340 who faintly resembles the classic C size, also the 18350 both with flat noses, and with button noses. Those two seemed almost D sized.
erco mentioned early on that he uses the 14500 in AA style holders. I'll give him credit for that one, even I didn't come up with that one.
Those batteries I bought without proper thought will become a portable power-supply for my normal work. I might try your idea erco, if I can track down the size but without the available charger who they also sell with them.