Grid Charger for Dummies
 

Hello All- I just purchased a 2008 Civic Hybrid and I am getting the PAO7F code. I have read several articles on building your own grid charger and discharger. Can someone give me a detailed parts list and schematic? Thanks

Re: Grid Charger for Dummies
 

Check my sig. DIY for about $80.

Downside is the fan is PWM controlled, so you'll need to charge/discharge the pack outside of the vehicle as you can't drive the fan by feeding it 12V. It needs a 50% duty cycle PWM signal.

Re: Grid Charger for Dummies
 

You will find this thread very useful: https://www.greenhybrid.com/forums/f...charger-30096/

Thanks to S Keith, Hunter, P Perkins and others on this and other hybrid related fora I have "grasped the nettle" and built myself a DIY charger.
I am not tool shy but have or rather had limited knowledge of electrimagics :confused:, until now.
Building one wouldn't be possible without the help and support from the more knowledgeable members.:thumbs_up so, THANK YOU!!!

So far all is good, the thing works but for taking my 08 Civic (48k miles) off the road for long enough. I aim to give it a proper 24hr. charge this week-end though.

I have incorporated a digital temperature meter (12V DC) into the design, with a long wired probe attached to the bottom of the battery pack so, temp. monitoring needs just a glance. :lightbulb
To help resolve potential cooling problems I have inserted a 90mm computer case fan into the pack exhaust duct behind boot (trunk - for youall across the pond :) ) liner. It too is powered by the 12V DC power supply and lives in the the "wide" section of the duct where foam muffler used to sit. It's a tight fit but the plastic is pliable enough to adapt to its width. Supply wires simply come out the end.

Fingers crossed it will help prolong my battery's life.

Re: Grid Charger for Dummies
 

Just some pics I took while installing the harness.

Attachment 2328

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Re: Grid Charger for Dummies
 

Very nice.

Could you provide links to the temperature sensing hardware and that fantastic voltage display?

Thanks,

Steve

Re: Grid Charger for Dummies
 

Hi Steve,

I bought the volt meter off eBay: http://www.ebay.co.uk/itm/2613529818...%3AMEBIDX%3AIT
It needs 5V DC so, I cracked a mobile phone wall charger and used the circuitry within.
If I was to build another, I would get a higher rated meter, for until the charger is connected to the battery, the display shows EEEEE.E since its output exceeds 199.9 limit.

Here is a link to a temp. gauge: http://www.ebay.co.uk/itm/2817755520...%3AMEBIDX%3AIT
The probe lead was too short (less than 2m) but I used a length of 2 core cable to extend it.

The charger has been connected for over two hours now, started with 175.51V and 16.3 deg. C it's on 183.32 V and 17.6 deg C now.
I will turn the in-built fan on in an hour to check if it generates sufficient airflow to keep the temperature down. If need be, I will place another fan on the cabin intake grille.

Re: Grid Charger for Dummies
 

Thank you for the links... .XX accuracy on 199V is fantastic.

If your sensor is at the bottom of the pack, you need to turn your fan on immediately.

All your initial heat will migrate to the top of the pack and your sensor will never pick it up. Given your relatively low ambient temps, it's likely not an issue after so short a charge, but at 4°C ambient, I had a Prius pack hit 56°C overnight without cooling.

Re: Grid Charger for Dummies
 

Thanks for the tips Steve,
I too figured the positionioning of the probe wasn't ideal but couldn't be bothered to pull the pack out again.
Swithched the fan on and the temp. reading shot up from 18.3 to 28.5 deg C in a space of a couple of minutes as a result of hot air being drawn past the sensor but then came down.
Anyway, provided the fan is turned on at the start, the resulting airflow keeps the temperature in check.
It's on 20.2 deg. C at the mo after 6hrs. I will do one more reading in half an hour and leave it for the night, should be finished in the morning :moon:

Re: Grid Charger for Dummies
 

It's actually where it should be. You don't want to break the seal the top of the pack makes with the inlet.

You just need to turn the fan on w/the start of grid charging. These packs are insulated like beverage coolers.

I really like your solution. I'd love to see how you attached to the exit duct.

Thanks,

Steve

Re: Grid Charger for Dummies
 

Hi Steve,
Thanks for the complement.
The 90mm fan sits in the fat, "box" section of the vent tube in pic.3. It's not very powerful, draws only 0.5A but seems to be doing the trick, above all it shouldn't impede the operation of the car fan. The Seaflo 12V fan I originally bought for the purpose draws nearly 3A and shifts masses of air as it's designed for boat engine rooms. Sadly, I found plumbing it into the pack vent tube a little difficult, might re-visit it later.
Warm air from the pack vents into the void behind the liner as nature or Mr Honda intended.

Before going to bed last night, I placed another PC fan on top of the pack vent grille to push some air into the pack and increase the flow - just in case.

Now for the results.
Started with 175.51V at 16.00hrs and reached 186.92V by midnight. The next reading at 7am showed 187.38V and the same at 8 and 9 am so, I switched off at 9.15am as we had to go on a visit.
Came back at 3pm, the voltage dropped to 177V (?!?) reset the battery and let the car charge itself to 8 bars, at which point the pack showed 181V.
Does this sound right?
Here are some pics of the charger and leads, I deliberately used bright colours to make the harness stand out. When not in use, it sits hidden behind the liner.
Attachment 2335
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