Here’s a little hack for the AlphaSmart Dana that will both improve battery life and allow you to future-proof your Dana’s power needs in the event that AlphaSmart someday stops selling replacement battery backs.
AlphaSmart rates the life of Dana’s rechargeable battery pack at 25 hours, but users generally do not see that kind of life since the Dana’s battery pack gradually loses its charge when sitting. The actual run time varies widely, depending on how soon the device is used after being charged and how long the device sits between uses. A freshly charged Dana will still last far longer than a laptop computer, but the gap between the two will narrow the longer the devices have been sitting.
There are two reasons for Dana’s power drain. First, as an older Palm OS device, Dana needs a constant trickle of power to preserve the contents of RAM. The second reason is the nickel metal-hydride (NiMH) cells used in the Dana power pack. One of the disadvantages of NiMH batteries versus traditional alkaline cells is their slow self-discharge, which gets more pronounced as the cells age. The gradual self-discharge is probably responsible for more dead-battery surprises than the power needed to keep the RAM alive. Happy Dana users are frequent users and frequent re-chargers.
In the last few years, developments in battery technology have led to a new type of NiMH battery that has a miniscule rate of self-discharge. Manufacturers claim that these “Low Self-Discharge” (LSD) batteries retain 85% of their charge even after a year of storage. The LSD cells can be recharged 1000 times and are completely compatible with any charger or device that uses the older NiMH batteries, including the AlphaSmart Dana. As a bonus, the new NiMHs also have a larger capacity than the older cells used in the Dana battery pack. Dana’s cells are 1600 MaH, while LSD batteries are usually 2000 MaH. The larger capacity, combined with the almost non-existent self-discharge, make LSD NiMH cells the ideal choice for powering Dana.
Unfortunately, you can’t simply plug the new NiMH cells into Dana’s battery slot. The battery slot is wired for alkaline batteries, a feature that allows users to slap in a set of standard AAs when the rechargeable pack goes dead. The Dana does not correctly read the voltages of NiMH cells plugged into the battery compartment, nor would the device recharge cells through the compartment wiring. Instead, there is a separate power connector for the rechargeable battery pack. In order to use the new LSD cells, one needs to get them plugged into this separate power connector. One way to this would be to rebuild the battery pack with the new cells. A second way is to wire the alkaline battery compartment to the power connector used for rechargeable packs. I chose this second method, essentially turning my battery compartment into an open-door rechargeable battery pack that I can install new cells into whenever I like. Of course, I must be careful if I ever decide to put a set of alkaline cells in the rewired compartment. They’ll run the device fine, but it could be dangerous to plug in the charging cable while the compartment contains alkaline cells. Not a problem for me. Most of my gadgets are recharge only anyway. I’m used to it.
To re-wire the battery compartment, you’ll first need to take apart the Dana case so you can remove the motherboard. You can see the power connectors from the battery compartment, and the separate one that plugs into a rechargeable pack. What we’re going to do is clip the black compartment wires off of the board, and wire those connectors to the wires used for the rechargeable pack.
Closeup of the pre-snipped wires.
Here we are with the wires cut. You will also need to strip the plastic coating from the ends of all wires.
Next we have to wire the flat battery connector to the red recharge line. With the wire ends stripped of their plastic coating, you can twist the two together pretty easily. For the spring connector, I had to add some extra wire to the black line since it wasn’t long enough to reach the other end of the battery compartment. I took an extra length of wire, stripped the ends, and twisted it together with the short black wire. I twisted the spring connector onto the end of the longer black line.
To finish up, I covered the exposed sections of twisted wire with a bit of electrical tape. One must be careful not to use too much tape; it could thicken the wires to the point where they can interfere with the case halves fitting back together.
And here we are with the case put back together and the new cells in the regular battery compartment. The compartment now serves as a rechargeable battery back that can have its cells replaced anytime. Based on how well the LSD cells (Sony CycleEnergy) work, I do not think I’ll ever even need to rely on a spare set of alkaline cells. The battery life that I’m seeing with this hack is really quite incredible. I’ve let this Dana sit for three weeks at a time, and can come back to a system that still has a bit of juice remaining. No more dead battery surprises!
You’re pure genius! I bought a Dana off ebay, thinking the batteries wasn’t going to be an issue…but it was. See, I’m a reporter and I attend many political meetings and such. I can type just about as fast as most people talk. It got to me after a while how I wasn’t sure whether or not the remaining juice in my Dana was going to last through the next meeting – so I’d wind up tossing batteries that were still partially good. Your hack took a half-hour over the weekend, and it works like a charm! I’m so glad that I stumbled onto this. You could make good money fixing up Danas with this hack. I wonder why Dana didn’t sell their units like this to begin with. You rock!
Thank you, thank you, thank you for sharing this hack. It’s really easy, I could usw my old soldering gun, it was fixed in 20 minutes and it’s working really great.
Just did it and it works wonderfully!
Thanks
This is awesome! I bought a Dana a couple years back but never used it because I was so disappointed by the crappy battery it had and the fact that I’d lose everything. Seeing this got me to buy a new one though, and I’m so glad that I did. Thank-you for making the Dana a worthwhile and usable device for me!
Great hack. Works like magic. You’re right about the black tape… don’t use too much or the case has a hard time fitting back together.
Just finished up, and my Dana is working perfectly! Thank you so much for this idea!
One thing: I was able to hook it all up without removing the board, so, less work…
Love it!
I’ve just bought a Dana on ebay, and quite possibly the battery will be dead so this should be useful, thanks! Just one question, is the rechargeable Dana battery pack internal, or does it sit in the battery bay?
The pack sits in the battery bay. You’ll see that when you get your Dana. (If yours comes with the pack, that is.)
Thanks for stopping by!
Dear Vance Fry, I did the internal rewiring of one of my Danas, and the modified Dana did not charge the batteries! However, I tinkered so more and found that the installed NiMH batteries, which were new but unused for over a year, had some corrosion on the + polarity terminal. I cleaned them with sandpaper, and now it works. Big question is how long they will stay up … BTW, do the NiMH batteries have the “memory effect” defect that plagues the older Nickel-Cadmium rechargeables? In other words, is harm done by topping-off the charge on the set of NiMH batteries??
QUESTION: WHICH STYLUS FOR DANA? IIn my little “fleet” of ten Danas, some of them are missing the STYLUS. On Ebay, none of the replacement styluses are identified for Dana. My Palm Vx stylus and my Palm Tungsten E stylus fit loosely in the Dana’s slot for stylus. Which Palm-model would have the perfect fit stylus for Dana? Thanks, Stephen Buggie, Gallup NM June 11, 2011
You won’t harm the cells by topping them off. And if they wear out in a few years, buy a new set.
I don’t think any Palm styluses will fit in the Dana slot. I think they’re a custom job. You can buy a ten pack from Renlearn:
http://www.renlearn.com/store/storeitem.asp?item=ACCSTY10&id=3248&type=0&c=MP+73%3A24%3A5+1102%2F11%2F6
Are you saying that you can break an Alphasmart by putting rechargeable batteries in it? I’ve started having problems transferring data off mine and I recently put rechargeable batteries in there.
Addition: I’ve been using an Alphasmart 3000.
You won’t be able to break an AS3K with rechargeable batteries.
Thank you, this is great! I’ve just done this with my Dana.
I thought I’d share that instead of connecting to the battery case the wires (A) which are directly connected to the motherboard, I detached the wires (B) from batteries in the rechargeable pack that came with the Dana, and connected those wires (B) to the battery case, after cutting away the wires (C) originally attached to the battery case.
The battery wires (B) were kept connected to the motherboard wires (A) by the original power connector.
I might not even have had to take off the whole back cover doing it this way, just the battery compartment cover.
Hi,We tried this, but now the on/off switch does not seem to work. When I put the batteries in it came on and would not go off. Any suggestion?
You mention that you need to add a length of wire to make sure it can reach the other end of the battery compartment. I know very little about wiring, so is there a particular type or size of wire needed for this?
charburchak, I just used the pieces of wire that I cut off the motherboard that were originally wired for alkalines. The gauge is fine.
Well I finally received the alphasmart I ordered above (long story), and I’m ready to hack.
First, I’ll find out soon enough I suppose, but is the battery compartment ground connected to the battery pack ground? In that case, I think I can just cut out the positive “blanking plate” from a dead battery pack, and insert it into the battery compartment, and still leave everything connected? ie no surgery required to the AS itself.
Also, has anyone looked at adding backlighting, eg some LEDs around the display, or an electroluminescent panel behind etc?
I’m looking at installing ssh and a few similar things, I gather TuSSH supports alphasmart.
Of course the big limitation is WEP only 802.11b, but I also have an old palm bluetooth SD card, and my aim is to experiment using the AS as an “intelligent keyboard” that you can also take with you. In the simplest case it could be a “KVM” type keyboard with hosts listed and selectable on the touchscreen, for example.
Jack
I bought this Alphasmart Dana Wireless off eBay and decided to hack it to accept three rechargeable AA batteries, per your directions.
But when I opened the unit up, I saw that there was ample space for one more AA battery. Strangely enough, there’s even a plastic slot at the end that can accept the springy “negative” battery terminal after the latter has been removed from its original position.
Any worries about “frying” the circuit were quickly dispelled when I realized that four rechargeable AA batts, at 1.2v apiece, would only deliver 4.8v of juice –whereas the Dana happily accepts 5v via its inbuilt USB ports. And, in any case, the output of the Dana’s factory-issued charger is a surprising 7.5v!
Pictured here ( http://farm8.staticflickr.com/7169/6418696231_c3d0a16e4e_b.jpg ) is my own mod, based on yours but with the “negative” terminal moved to the end slot. Note that the original plastic slot has been melted away and filed down to allow the fourth AA battery to easily slide in and out of place.
Hi, TJ Dimacali.
What has been your experience with 4 batteries instead of 3? Does it go longer between charges than the original mod? And for the life of the device itself, I wonder if this is actual something that should be done anyways, as the NiMh at 1.2v are putting out 3.6v instead of 4.5 with the alks. 4.8v seems closer.
“seems closer”…sorry for the obvious
Okay, did a mod with 3 AAs one one Dana and 4AAs on another. The backlight is noticeably brighter on the mod with 4AAs in a moderately dark room. It’s not dingy anymore.
Hi, Pete!
Sorry for the very late reply; I haven’t been checking here of late
I seem to have problems charging the Dana un 4AAs. Long story short, plugging the device in (via USB or direct charging adapter) doesn’t fully charge the batteries —the charging light suddenly goes green, indicating a full charge even though the batteries are still weak.
My guess is that the Dana senses the higher output of the 4 AA’s but still thinks that there are just 3AAs in there, so the charging cycle gets stopped before the 4AAs get fully topped up.
Does anybody have any ideas how to fix this? Theoretically, maybe a resistor or a reverse-biased diode can be put in place to make the “load” look like 3 AAs again?
Thanks, TJ….good info!
I charge the batteries with a dedicated battery charger, and switch out an extra set of freshly charged Eneloops while plugged into a USB charger so I don’t lose data during the switch. So far I’m digging the 4AA setup, though on the Alphasmart flickr forum there was some concern voiced over what kind of stress this may be placing on the device. So far so good, though (3 weeks).
Another thought on the battery charging situation, TJ. Did you leave it to charge for a while and check the voltage indicator that you can bring up on the Dana screen? I wonder if it was still charging even though the green light was showing.
I guess it’s a bit of a moot point though, as it’s better to charge the batteries with a dedicated charger that will be charging the battery at a lower mha rate than the Dana will (healthier for the batteries).
Hi Pete!
I actually left it to charge overnight, but as soon as I unplugged it it would die on me
Even though the green “fully charged” light was on.
I got a Dana from eBay and was disappointed with the battery life, so I ordered a replacement battery pack from alphasmart.com. I’m _pretty sure_ that the new battery pack is LSD nimh, because the battery life is _really_ good. I haven’t asked them yet, but anyone who wants better battery life, better than the maybe 72 hours standby, 3 hours work that I was experiencing, to get the new battery pack from them direct.