Q. My dad gave me a Sony AIBO ERS210 robot dog that he received as a
bonus at work many years ago.
The unit seems mostly new, but I
think the battery is shot. Is it
possible to rebuild this battery
pack? The places online that sell
an AIBO battery seem to be very
A. Agreed! Replacement batteries for obsolete devices are overpriced —
often more than the cost of the
entire used device. It appears
that a refurbished battery may
be your only option. If you go to
they will refurb your battery for
$70, or sell you one outright for
$129; eBay listing
#162377316342 is for a
dead/will not charge ERA-201B1
battery for your ERS210 for $39
(!), but that’s like a “core” for
rebuilding. Pricey in my book,
but AIBO is a classic robot
and definitely worth
Personally, I’m handy
and fearless and love a
challenge, so I’d take a shot
at repairing it (I have
repaired countless iRobot
Roomba NiMH batteries).
Best case, this results in
an ugly hacked battery pack
which works (not that you
see the battery in use).
Worst case, it doesn’t work
and I’ve destroyed the core
value, so my only option
then is to buy that $129
Got mad hacking skilz?
Take a look at Figure 6 and
proceed at your own risk ONLY if you
are very skilled with hand tools and
The pack uses four Li-Ion 18500
cells with solder tabs which will cost
over $5 each ( https://www.amazon
There is an internal PCB (printed
circuit board) which may or may not
be damaged — another gamble.
Replacing the cells starts by
CAREFULLY prying, breaking, or
cutting the plastic case open
(Dremel slitting saw or X-Acto®
razor saw). DO NOT cut into or
damage the old cells. That’s very
hazardous for leakage and fire
The case could be either
snapped or glued together, so
you’ll need to figure out the best
way to disassemble it. The critical
area to preserve is the battery
connector. Don’t damage that in
Once it’s open, take several
close-up photos of all the
connections to aid in
reassembly, and start swapping
cells. Pay attention when
soldering! Sometimes the solder
joints need to be very flat for
proper fit on reassembly.
squeeze everything back
together. Check for proper fit
and avoid short circuits!
Hold everything together
with electrical tape initially and
test-fit the battery in AIBO and
see if it will charge. If you’re
all good, reassemble the
plastic case more
permanently with electrical
tape or CA glue.
Homemade repairs like
this are ALWAYS a bit risky,
so be vigilant and use
“forever” caution when
charging and using the
Q. I’ve been interested in creating a
telepresence robot that can
move around my house and
allow me to see/hear what’s
happening there. Most
robots seem to be either toys or super
I’d like to roll my own, and I have
a Parallax Stingray robot that seems to
be a nice solid chassis to start with.
10 SERVO 05.2017
Figure 6. Aibo battery.
Figure 7. Stingray.
Figure 8. Rovio.