What type of connector does a Prolong Charger/Discharger use?

I'm about to buy a Prolong charger for my Prius 2010. I think I don't need the discharger because I already have an electronic load that can easily be programmed for a 84-134V, 1A rate. But I would rather not modify the existing harness and just create a pigtail to connect the load to it.

I've already sent an email to hybridautomative to see if I can just purchase it. But in case they don't sell it separately, does anyone know the name of the connector so I can just order it from Digikey or Mouser?

 

The pictures I saw online of the insides of the charger/discharger did not inspire confidence either.

From what I can tell, the Prolong Charger is just a trickle charger, relying on the fact the NiMH batteries can be charged indefinitely at 0.1C (or 650mA for the 6.5Ah blades), so leaving it plugged in for 4-6 hours after the voltage stops rising forces the weaker blades to charge fully without damaging the fully charged blades.

I'm actually thinking of using a high voltage bench supply. I can just set it to 650mAh constant current mode, with a limit of 240V and 24H for safety. The cool thing about using this setup is that I can hook it up to my computer and plot voltage and current charge/discharge curves, as well as automatically kicking off the charge/discharge cycles.

Thanks for the link. Let me go through the thread to see if I want to go this route. If I was building my own harness, I can basically use any matching connectors that is rated for the voltage/current.

 

Quick correction. C/10 is the standard (not fast) charge rate. Trickle charge for NiMH is C/20 to C/50, or < 325mA for the Prius.

 

@Tombukt2 If you just want to turn the charger off after a set time, these chargers don't draw much power, so you can use any 120V mains timer. Just make sure you have a diode in the output so the back voltage from the battery doesn't damage the charger when it's turned off.

 

@PriusCamper Very interesting thread you sent me, I'm still going through all the linked threads and wikis. I did not know that there was such a large community for DIY Hybrid Battery Conditioners.

FYI, I got a reply from George from Hybrid Automotive. He cannot help me make any modifications (even telling me what connector they use) due to liability. I guess I can't fault them for this. Unfortunately, it means that I'm better off building my own charger, as I will get no support and possibly void the warranty if I use theirs.

Using an electronic load as a discharger actually simplifies the whole system quite a bit.

All I need is the 350mA constant current source (Mean Well LPC-100-350 or HLG-80H-C350A), hooked up in parallel. My load is a PEL-3032E, and it displays the voltage even when the input is disabled, letting me monitor the charge voltage. I can't monitor the charge current without also hooking up an ammeter, but I don't think it's necessary as it's pretty much going to be the trickle charge of 350mA if battery is less than the 357V limit of the source.

Then built the harness with the 2A fuse, source pigtail with reverse voltage diode/bleeder 100k resistor and I'm done.

For the charge phase, turn on the charger, turn on the load (but not enable the input), monitor the voltage until it stabilizes for 4-6 hours.

For the discharge phase, turn off the charger, set the load to sink 1A until 196V, sink 0.5A until 140V and 0.2A below 140V. The load is pretty flexible, so I can play around the settings, possibly making it continuously vary from 1.5A to 0.1A as the voltage drops.

For the fan, I'm just going to hook up my 0-12V bench supply. I'll adjust the output to run at a decent speed, but not at full blast so as not to stress the fan.

 

@The Jovester thanks for info about the Hybrid Automotive connector. I don’t need to use the same connector anymore since I’m making my own charger.

I’m going to use the Ideal PowerPlug Luminaire Disconnects recommended in the linked Grid Charger threads instead. The main reason being that they are finger safe in both connectors, important for me as both the charger and battery sides have over 200V. They are also readily available at my local Home Depot or Lowe’s.

On a side note, I finally managed to find the correct connector for the fan blower, so I don’t have to splice in my own connector. Here are the part numbers in case anybody is interested. They are readily available at Amazon, AliExpress, Ebay or hi-1000 (if you want OEM instead of clones).

Toyota 90980-10795
Sumitomo 090 type 4 pole TS series F (OEM equivalent)

 

Just following up since my mouser order finally arrived this week. I've yet to make the Prius harness, but I've wired up the Mean Well CC Power Supply and the Electronic Load. Here are some pictures.

The wiring is pretty straightforward.
Input is straight to a plug. I've decided to use a GFCI plug since there is no ground. It can also serve as a power switch since it defaults to off, and you have to press reset to turn it on.
Output is wired to two Powerplug disconnects. One goes to the Electronic Load, the other goes to the Prius harness.
There's a 4007 diode in series with the positive to protect the power supply from the back voltage from Prius battery when it's powered off.
I did not put a bleeder resistor at the output since I do not have any exposed wiring where I would need the voltage to drop quickly. I did a quick test and the Mean Well naturally drops from 289v to 50v in 15s, and 8v in 30s when powered off. That's acceptable to me.
FWIW, I'm not a big fan of the Ideal Power Plug disconnects. They are push in style quick connector, good for solid wire, but you have to tin stranded wire, so you don't save any time. Even tinned, the stranded wire tends to bend when you push them in, so I'm never sure they grabbed properly, and kept pulling them to double check. I'm not confident that they won't pull out eventually, exposing the high voltage wires. In hindsight, I should have went with the locking round connectors I originally asked about. I may redo all the connectors eventually.


I ran a few tests on the bench with just the Electronic Load connected.

With the Load disabled, it shows a no load output of 289.34v.


With the Load drawing 0.1A, output drops slightly to 289.02v, drawing 28.874w.


With the Load drawing 0.35A, output drops further to 288.95v, drawing 101.06w.


With the Load trying to draw 0.5A, it goes into Unreg mode, and constantly backs off to protect the power supply.


With the load set to 200v, output drops to 200.05v, pulling the max rated 351.85mA current, and drawing 70.386w.


Next up, the Prius wiring harness, it's also pretty straightforward, just a straight connection from the disconnect to the negative and positive terminals of the battery, with an inline 2A DC fuse as close to the positive terminal as possible. I bought quick blow fuses, not sure it's correct. I'll find out wether there is a large in-rush current that trips it right away when I finally hook everything up.

The fan connectors from Japan haven't arrived yet, so I'll have to jury-rig something from the 0-12v bench supply to power the fan while charging the Prius.

I'll keep you all posted when I start charging for real tomorrow.

 

Sorry for the late reply. Hooking up the harness was frustrating, as it's very tight, and I dropped a nut and had to take the back seat out to get to it. But it's done! Lots of pictures.

Harness. Just a straight connection with an inline fuse.


Installed.


Fan connector. Just a straight connection, but with 2 pigtails for ground, per wiring diagram in other DIY grid charger threads.


The correct connectors from Japan haven't arrived yet, so I just pushed in the spade connectors. Seems secure enough as long as I don't move the cable around too much.


FYI, the fan draws 1A at 9V, and 1.6A at 12V. I had conflicting info from other threads, and I was worried my power supply did not supply enough current (max 2A).


Battery current charge is 222.76V, with nothing connected.


Everything hooked up. I made the cables a little too short, so I had to stuff everything in the trunk. I will probably make some extensions to move everything outside.


We're live! Battery voltage climbed slightly to 223.41V. I don't have a current reading, but it should be 350mA.


Now I just have to wait for the battery to charge fully, and keep it there for 4-6 hours to top off all the weak cells.

 

Seems like my battery is in bad shape. It charged to 237.64V much faster than I expected, and stayed there. I will let it run for a few more hours to top up the weak cells, then switch to discharge at 350mA overnight.


I definitely need an extension cable. The hottest thing in my trunk is the Mean Well supply, at 138.2F. Ambient is 84.9F.


The battery is at 98.2F. It was approaching 100F earlier, so I had to bump the fan up to 12V and open the passenger door by the intake.

 

I left the charger on overnight, and it went up to 239.94V.


I added an extension cable so I can move everything out of the trunk.


Hottest thing in the trunk now is the blower, at 84.7F.


Discharging at 350mA, with termination at 134V. I decided against programming the Electronic Load to discharge at different rates depending on the voltage, as this is my first time doing this, and I wanted to keep it simple.

 

One problem with an Electronic Load is that once it hits the target voltage of 134V, it will reduce the current draw to maintain that voltage. But at low current draw, the Prius battery can maintain that voltage for a very long time.

I decided to finally stop discharging once it dropped below 100mA.


Voltage bounced back up to over 140V when the load was disconnected.


Turned the Mean Well supply back on for the 2nd charge cycle. Unfortunately, there was cycling (voltage would bounce up and down as it rose) until it stabilized at around 160V. I think I'm running into the hiccup mode short circuit protection in these supplies. I was able to just wait it out as the voltage rose quickly to 160V even with the power supply constantly resetting. But I'll need to figure out how to workaround this when I do the 2nd discharge cycle down to 101V. I'm thinking of making a y-cable to hook up the Electronic Load in series set to 100V, so the combined battery + load voltage is 200V, well beyond the 143V hiccup mode protection of the supply.

 

Dongles!


First, a Y cable so that I can hook up the Electronic Load in series to increase the voltage shown to the Mean Well supply, and prevent it from going into hiccup mode.

But then I realized that I can also use it to hook up my multimeter in series to measure the current, so I made another cable with the male disconnect on one end, and shrouded banana plugs on the other end.

But wait! This same cable can plug directly into the harness and measure the voltage of the hybrid battery. Much safer than trying to juggle regular multimeter probes across high voltage lines.

 

I was reading the manual to figure out how to program a more sophisticated discharge profile, and it turns out that this type of device is actually designed to test batteries and chargers, so it's trivial.

I set it to battery discharge mode, CR@400ohms (so the rate slows down from 600mA@250V to 252.5mA@101V to 210mA@84V, another choice was the safe C/20 rate or CC@325mA), terminate at 101V or 6Ah or 24h, whichever comes first. It shows the current voltage, amps, watts, time so far, discharge capacity so far in Ah or Wh. I can also hook up a computer to the USB port to record the discharge profile. Really cool. This is definitely the way to go, much easier than swapping light bulbs.

 

It says it discharged to 101V overnight in 9:09:22h, but the current voltage says 174.06V?


I discharged it again to 101V just to be sure. This time, I saw that it did discharge in 0:22:47h , but climbed quickly to 150.64V once it stopped discharging, so I guess this is normal.


I figured out what the 'TEST results' button does. Not too useful, since it just shows a normal CR discharge curve, but very cool nevertheless.


Now onwards to the last cycle to 84V.

@PriusCamper thanks so much for the links to the DIY charger thread, and getting me down this rabbit hole. I noticed that the Olrowdy thread suggested discharging to almost 0V, as long as you are very careful not to reverse charge above 350mA, and he has better results discharging this low. Hybridautomotive also originally suggested discharging to 17V, but suggests 84V now. Do you think it's worth it for me to try this, given that the Electronic Load gives me the ability to precisely control the discharge current? What voltage do you use when you recondition your Prius battery?