DIY cranking or booster battery pack

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MikeT
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Re: DIY cranking or booster battery pack

Post by MikeT »

First test of C5 maintenance charge currently in progress.
Despite the lack of under-bonnet space, I managed to squeeze in 2x 4S 5A LiPo packs, a parallel charging board and Pb charger within the short constraints of what cables I have. As more parts/accesories arrive I should be able to make it more compact and secure but for now I'm just grateful I can lock the car up, retreat indoors and keep warm while it does it's thing.

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EDC5
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Re: DIY cranking or booster battery pack

Post by EDC5 »

Will you be able to get some pictures of the setup? as I'm very interested in this :)

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Re: DIY cranking or booster battery pack

Post by MikeT »

Slight hiccup earlier, though I'm not surprised (it's not a maintenance/float charger) and put it down to the initially awakened ECU's going back to sleep messing with the charger's algorithm as it cut off after only 53 mins and 1.7A announcing the battery was "Full"...
From an intial resting voltage of 12.1V? I don't think so.
A subsequent restart of the program this time without waking the car up shows it's now taken another 3A @14.7V with the source LiPo's still reading 3.78V per cell (about 50-60% capacity left).

All in all I call that a very successful first test and there's much scope for improvement. Can't but help love the lighter lithium's even more now.
Last edited by MikeT on 29 Oct 2018, 23:30, edited 1 time in total.

MikeT
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Re: DIY cranking or booster battery pack

Post by MikeT »

EDC5 wrote:
29 Oct 2018, 22:49
Will you be able to get some pictures of the setup? as I'm very interested in this :)
I can do, Ellis but don't expect it to look pretty or even sensible :lol: , I'm just trying to gauge the power source potential at this point.

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EDC5
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Re: DIY cranking or booster battery pack

Post by EDC5 »

That's no problem at all :D

MikeT
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Re: DIY cranking or booster battery pack

Post by MikeT »

Will do tomorrow, am just about to crawl under the duvet for the night, brrrr!

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white exec
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Re: DIY cranking or booster battery pack

Post by white exec »

Could you post a circuit diag of the set-up, Mike, if not already patented?!

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GiveMeABreak
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Re: DIY cranking or booster battery pack

Post by GiveMeABreak »

I was looking at one of those solar panel trickle charging units that plug into the diagnostic port - started looking at the AA ones, seemed ideal - but then went to Amazon to get a better idea of them from the reviews - and I always look at the 1 star ratings first and was quite shocked at some of the horror stories - wires melting / catching fire or actually discharging the battery during the night, so am now undecided:

https://www.amazon.co.uk/product-review ... geNumber=2
battery trickle.PNG

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white exec
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Re: DIY cranking or booster battery pack

Post by white exec »

That's enough negative reviews to tell me to keep well clear! :cry:
There must be a list of recommended ones somewhere on the web - try the RAC site, or Which? or Cnet?

Always thought the ideal use for an otherwise unwanted sunroof!

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Re: DIY cranking or booster battery pack

Post by MikeT »

I bought one of those solar panels from Maplins about 12 years ago and it killed the battery beyond recovery within a day or two.

The C5 is covered in ice! What sort of winter are we heading into?
Battery reading 12.0V after unlocking, waking up ECU's and running the hydraulic motor.
It's back on charge now with same setup as yesterday. I can close the bonnet but haven't fully latched it down. That way I can lock the car and periodically check the status without waking up the systems.
Capture.JPG
LiPo's on the left with individual voltmeters plugged in connected to the parallel charging board inthe middle powering the Imax charger on the right running the Pb Charge 6S program at 5A max with no time or amperage cut-off limit until it considers it fully charged.
Capture2.JPG

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GiveMeABreak
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Re: DIY cranking or booster battery pack

Post by GiveMeABreak »

white exec wrote:
30 Oct 2018, 09:37
That's enough negative reviews to tell me to keep well clear! :cry:
There must be a list of recommended ones somewhere on the web - try the RAC site, or Which? or Cnet?

Always thought the ideal use for an otherwise unwanted sunroof!
Funnily enough that was an AA one Chris :rofl2:

However, the other down side is that because they have to connect to the diagnostic port - and yes, where is the diag port on an X7? - right in the central arm console under some rubber seal - it's not going to be very practical leaving that on with the arm rest up in the air showing all my junk off to the neighbourhood! :-D

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Re: DIY cranking or booster battery pack

Post by GiveMeABreak »

MikeT wrote:
30 Oct 2018, 09:44
I bought one of those solar panels from Maplins about 12 years ago and it killed the battery beyond recovery within a day or two.

The C5 is covered in ice! What sort of winter are we heading into?
Battery reading 12.0V after unlocking, waking up ECU's and running the hydraulic motor.
It's back on charge now with same setup as yesterday. I can close the bonnet but haven't fully latched it down. That way I can lock the car and periodically check the status without waking up the systems.

LiPo's on the left with individual voltmeters plugged in connected to the parallel charging board inthe middle powering the Imax charger on the right running the Pb Charge 6S program at 5A max with no time or amperage cut-off limit until it considers it fully charged.
Blimey Mike - there's no way I would contemplate having anything like that under the bonnet - knowing my luck I'd forget about it and drive off with all that gubbins under the bonnet and probably go up with a bang down the lane!

Reminds me of a bloke who put a blanket under the car during a bad winter - got covered in snow and he completely forgot - started the car the next morning and ended up with a blanket in the engine all shredded and caught in the belts and well, say no more, but the car was knackered and he wasn't too pleased!

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white exec
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Re: DIY cranking or booster battery pack

Post by white exec »

The apparatus behind the new batteries is presumably the Liposuction. :)

MikeT
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Re: DIY cranking or booster battery pack

Post by MikeT »

The C5's off the road due to a fluid leak and other needed repairs, Marc.
Chris, those batteries are about six years old though still good as new, unlike my 6 lead acid batteries.

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Re: DIY cranking or booster battery pack

Post by MikeT »

Got back from the doctors, the charger was once again showing "Full", this time after running for 123 minutes adding a mere 400mA with final battery reading of 12.6V.
Restarting the program resulted in an immediate "Full" stop again.

That's a huge relief, I've got a working, lightweight, portable, slow-charging system at least, and won't ever have to lug a big lump of useless lead indoors (and back) ever again. [-o<

The data suggests just one LiPo should suffice (for the C5, at least).