Any time we hear from [Charles Z. Guan], we know it’s going to be a good feature. When he’s linking us to a blog post with phrases like “If you touch the wrong spots, you will commit suicide instantly”, we know it will be a really good feature. [Charles] is no stranger to Hackaday – we’ve featured his GoKarts, Quadcopters, and scooters before. He was even generous enough to let a couple of Hackaday writers test drive ChibiKart around Maker Faire New York last year.
This time around, [Charles] is working on a power system for chibi-Mikuvan, his proposed entry of the Power Racing Series. He’s decided to go with a used battery from a hybrid vehicle. As these vehicles get older, the batteries are finally becoming available on the used market. [Charles] was able to pick up a 2010 Ford Fusion NiMh battery for only $300. These are not small batteries. At 20” wide by 48” long, and weighing in at 150 pounds, you’ll need 2 or 3 people to move one. They also pack quite a punch: 2.1kWh at 275V. It can’t be understated, taking apart batteries such as these gives access to un-fused lethal voltages. Electrocution, arcs, vaporized metal, fire, and worse are all possibilities. If you do decide to work with an EV or hybrid battery, don’t say we (and [Charles]) didn’t warn you.
As [Charles] began taking apart the battery, he found it was one of the most well thought out designs he’d ever seen. From the battery management computers to the hydrogen filled contactors, to the cooling fan controller, everything was easy to work on. The trick to disassembly was to pull the last module out first. Since all the modules are wired in series, removing the last module effectively splits the pack in half, making it much safer to work on. The battery itself is comprised of 28 modules. Each module contains two 4.8V strings of “D” cell sized NiMh batteries. The battery’s capacity rating is 8000 mAh, and [Charles] found they still took a full charge. Since he doesn’t need the pack just yet, [Charles] removed the final bus bars, rendering it relatively safe. Now that he has a power source, we’re waiting to see [Charles’] next stop on the road to chibi-Mikuvan.
I know this is a relatively useless comment, but hey, couldn’t help but notice. These are the very batteries we build at my plant!
any chance you’re giving out free samples?
Ha! I wish. I’d love to convert my truck into a plug in electric!
I know you probably aren’t allowed to, but per chance do you have a datasheet of the cells used?
Nope, sadly. They’re made in a different department then the one I work in. The only secure access part that’s on the floor too. All I know for sure, is that they’re slowly replacing the human element working in that department, with robots, and that it’s one of two departments with A/C. Also no headphones in that area, oddly enough.
I wonder if these things could be used for a relatively high-power solar-charged or backup inverter. The built-in computer probably uses a CAN-bus interface. Does anyone know if you can make use of that?
“and worse”? I’m not so sure was worse than electrocution. An interesting tear down, but I’m not sure what I’d do with such a monster. 275 V. isn’t really conducive for a home shop built EV.
Worse would be, killing yourself, your family, your dog, burning your home to the ground etc….
Why wouldn’t it be? Just rewire them so you have a different voltage output. It’s just power storage.
I think he was trying to point out that Electrocution is death caused by electric shock, either accidental or deliberate. So nothing can be worse than electrocution/death.
I imagine slowly burning to death is worse than a quick electrocution? And we all know that’s a risk with batteries.
275V is indeed pretty ‘up there’, but just as doable with the proper safety precautions as any other ‘low but really high’ voltage system like 120V or 144V.
Besides, the idea is to use the modules in any fashion you choose, and for a smaller custom vehicle. If you tried to build an electric car with this battery, you’d probably get the advertised 6 miles of all-electric range they were sold as!
Worse would be a battery that rapes you before it kills you.
Its only 4.8v or so per cell, so VERY usefull!
Just make arbitrary sized packs.
PS.: Charles is EPIC, just spend a bit more time in is blog..
>”They also pack quite a punch: 2.1kWh at 275V.”
Can’t be. 150 pounds is 68 kg so the energy density would be less than 31 Wh/kg which is worse than lead acid batteries. If these are NiMH there should be at least twice the energy, and if lithium then at least 3-4 times the energy.
that is assuming that the 68kg is purely functional battery and doesnt include the supprting structure and various other parts.
If it has half dead weight, that’s a very poor design.
The actual webpage says the whole pack actually weighs 100 pounds, so that’s 46 Wh/kg which is still 30% lower than NiMH energy density, but that’s somewhat realistic.
It seems to me there are other requirements than pure energy density–charge time, longevity, holding charge in a wide range of temperatures, etc. I could see any of those being worth a tradeoff in capacity.
Then again, I’m not a battery expert. If you are, I’ll defer to your expertise.
I think you’re missing the ‘k’ prefix… kWh not Wh.
Tesla model S battery weighs in at 1225lbs!
There is a lot of overhead beyond the weight of raw cells. Each module inside is 3.66lb, of which around 5oz is the plastic spacer shell. If you consider it from the module level, then the specific energy is around 50 Wh/Kg. Still a bit on the low end for NiMH, but automotive grade cells typically sacrifice maximum capacity for more durability and wider temperature range. One of those sweet new 12Ah NiMH D cells would not last long in the typical automotive service profile.
All that destructive power, and he’s uses a $3 multimeter that has very little high voltage protection? eeeeek!
I was thinking the same, especially after having watched the EEV Episode where the Multimeter blows up.
The voltmeter shown is a member of the elite Harbor Freight voltmeter squad in my shop, and has been through many minutes of training and seconds of psychological, emotional, and physical vetting.
224 x 8Ah D-Cells for about $1.33 each, nice! These batteries are a gold mine!
My thoughts exactly. I was wondering if he’d sell me six of ’em, would make a nice pack to play with.
I thought that too. Almost any battery type except lead-acid gets expensive when you’re making a battery bank. He got a real steal buying the whole thing for $300. I should look for one of these packs if I ever make an electric vehicle.
It is quite nice, but bear in mind the idea of this exercise was to present an alternative to lead-acids for the scenario shown (the PPPRS league). If you were to build, say, an e-bike or scooter or recumbent, and were not artificially budget constrained, there are much better (lithium flavored) options for batteries. NiMH in any useful energy capacity is still quite heavy.
2010 Ford Fusion NiMh battery for only $300
Where? Junkyard?
It would be really funny if it would say “Uses 224 D batteries (not included)” in car details.
“Each module contains two 4.8V strings of “D” cell sized NiMh batteries.”
D cells? I am reminded of this electric car on Fernwood Tonight in 1977.
http://www.youtube.com/watch?v=9FsVjKewl_U
So this high tech hybrid runs on D size NiMh cells? There’s the solution to rapid recharging. Have an automated system to swap them out at a charging station that racks a few thousand cells being charged.
Open a door and connect up a “battery hose” with two conduits, one in, one out. A rotary magazine similar to that used on the General Dynamics GAU-8/A cannon would have the load swapped out real quick.
If you don’t need a fast charge, just plug in.
Then a hose breaks and you ventilate a nearby house and everyone in it. :V
These “cells” are torxed down to bussbars. Your drop-in setup would require tolerating “flashlight” preformance from a series of freekin contacts. I would hate have to shake or strike my car to make it go.
If anyone asks you just say its a classic british car.
Junkyards don’t know what to do with hybrids, so yes the parts are likely to be available in the bonepile.
I’ve also found that many electric bike and drill packs can be repurposed as EV drive if used as discrete units and the bad cell(s) brought back into balance with the others.
Quality LiFePO4s last forever even if the runtime sucks now, its normally balancing.
This approach might work with induction charging though, jsut have a bunch of identical packs with a distributed coil throughout the “stack” and magnets at the odd ends.
I used the Magtrix connectors from Maplins for a project and they outlasted the other components :-)
2.1KWh at 275V? Sounds like someone needs to get their hands on a 230V rated single phase AC frequency drive. If you hook it up to the battery (yes, you need a disconnect switch!) it should be within the operating voltage to power a 3 phase motor without issue. So, full power for an hour off a 3hp? 2 hours at 1.5 hp?
When I first read that title I interpreted it as “a battery manufactured by ford that is powered by fusion”, not “a battery from a ford fusion”. I was getting real confused at first, lol.
“The good news is this can power my scooter for a long time. The bad news is I’m being bombarded with neutrons. Eh, you take the good with the bad.”
“275V is indeed pretty ‘up there’, but just as doable with the proper safety precautions as any other ‘low but really high’ voltage system like 120V or 144V.” Agreed. With the proper safety gear it’s definitely do able. Great post!
275 V DC – a xenon flashtube converter, running off a single AA cell, will give that or more. Which I’ve been shocked by many times. It’s annoying but I wouldn’t describe it as lethal or ‘instant suicide’. That voltage would be good to run a computer power supply, set to 240 VAC.
I add brownout/voltage sag protection to computers by setting them to 240, then using a bank of 1,000uF 200.VDC capacitors in series/parallel fed by a voltage doubler wired full wave bridge. That has 320.VDC across it, and I’ve been shocked several times by that too.
DC is much safer than AC, I’ve been shocked by over 1,000 and nearly 2,000 VDC – 100.uF or so, as well, during ionization chamber experiments. And even 1,200.VAC a few times, from microwave oven xfmers (that hurts)
DC just creates a slight jumping sensation at the moment you make/break contact, with a heat sensation, whereas AC causes a violent jumping.
The higher voltages can create minor arc burns, depending on the duration and point of contact.
“a $3 multimeter that has very little high voltage protection? eeeeek!”
The probes/wires are rated for whatever voltage the meter will measure and then some (as a safety feature) typically 600.V or 1,000.V, some over 2,000.V
My tests of such wire shows they will handle 10’s of thousands of volts, just not for very long (leakage causes corona/ozone generation which degrades the insulation and it eventually cracks, which arcs)
The working voltage is determined by how bad this leakage is, along with how well the insulation can withstand the effects of ozone attack.
Standard wire is rated at 600 Volts because much above that, you start to get corona.
Low Voltage wire isn’t rated for even these voltages, because the insulation may have defects, while 600 Volt wire is (spot) tested for such defects.
“a 230V rated single phase AC frequency drive.. ..it should be within the operating voltage to power a 3 phase motor without issue.”
RMS isn’t the same as DC, the DC peaks are 320.V – a switching power supply will take that but a motor won’t, it will run hot and likely fry the windings, depending on load.
He would need a 320.V battery to properly supply an inductive electric motor. (a universal AC/DC brush motor would work though at reduced power – it doesn’t care about the waveform or peak vs RMS)
What about just X-raying the cells, you can make an educated guess on the internal geometry that way and also do XRD to identify various elements.
NiMH contain yttrium and Li-Ion contain cobalt which are quite dense so it is indeed possible to actually count plates then compute an approximate capacity.
I also read somewhere that Li-FePO4 (used in a lot of newer hybrids) can be scanned using a magnetic hysteresis setup as the iron (Fe) is magnetic depending on current charge state which is a function of voltage.
Interesting factoid, A123 apparently used this technique to sort between good and bad cells shortly before they went under (bad internal spot welds = random charge state)
I am actually working on a “sonic screwdriver” sized gadget that can scan FePO4 cells to not only see if one cell is damaged but allows monitoring of each and every cell in a given pack.. :-)