Mentioned in a thread earlier I found cheap power supplies on Ebay to lift a "to discharged" battery to a level where the bulult in one can kick in.
I have now tested on a Vectrix with a broken built-in-charger.
I did put two of those in series (30-90V 300mA):
I have about +20°C in the garage and the pack held 120V when connecting the chargers.
Now after (about) six days I can read 141V, and the pack shows +27°C.
24h x 6d x 130V x 0,3A = 5,6kWh went in to the pack.
Obviously the pack started to develop some heat, and I have no active cooling. But the top of the battery housing is dismounted.
Future plan is to use two of those chargers to equalize the pack over weekends, or when the temperature allows it without active cooling.
Thats very interesting - can you post more about the part number / specs of the LED power supply
Cheers
Chris
Search Ebay for "30-90v" and you find it.
Did more tests:
Have not used the bike since previous charge to 141V & +27°C.
When connecting chargers/supplies:
139V +17°C
12h later I interrupted at:
142V +22°C
Power added to pack: 0,5 kWh.
So I assume the pack is 100% charged since the pack starts developing heat (no active cooling).
Could probably be connected forever if the fans where spinning.
I also realize lower charging current means lower target Voltage, since those 300mA will probably never be able to rise the voltage to 154V.
I assume I now have a fully equalized pack...? Please comment!
24h x 6.5 x 0.3A = 46.8Ah
The battery should be full and equalised, but it loses a substantial percentage of it's charge in the first day due to self-discharge.
It will also take about 3-5 full cycles to regain it's capacity and "Ooohhmpfff".
This information may be used entirely at your own risk.
There is always a way if there is no other way!
I think to cell nimh full, we need more than 100%....
24h x 6.5 x 0.3A = 46.8Ah
46.8 Ah / 30Ah (nominal) = 1.56 = 156% full
This information may be used entirely at your own risk.
There is always a way if there is no other way!
I was thinking about 140%...do you think 1,56v is sure?
156% is more than 140%, so yes.
But, with very slow charge rates (0.3A = C/100) the charging is less efficient, so it might not be full. However, when the battery is warming up, it should be full.
This information may be used entirely at your own risk.
There is always a way if there is no other way!
What is warming for you? 25.ºC in cell when we have 20.ºc exterior?
Thanks for the post, just bought a pair of these.
What voltage did you set them to? I am guessing there are trim pots on them.
The voltage on these power supplies is not manually adjustable as the unit constantly varies the voltage automatically to achieve the fixed 300mA regulated current.
Although the combined voltage will probably exceed 180V without any load, the 300mA is not likely to be high enough to raise the battery voltage much above 140V (dependant upon the condition of the cells) so it should not be able damage the pack by overcharging it.
I bought four similar 320mA units with the aim of making up a switchable 320/640mA trickle charger for float charging and balancing, but I haven't wired them up and tested them yet. I am hoping that the battery will be able to dissipate the heat generated by the constant ~50 Watts (less than 0.5 Watt per cell) float charge without the need for cooling fans (especially in the winter) but I won't know until I actually try it.
Alan
You can also look at the MeanWell HVGC-150-1050A LED driver.
Just connect a Harting mail connector to it and you have a nice trickle charger.
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My contribution to EV in The Netherlands
- Novox C20
- Vectrix VX-1 Li+ my2009 #2791
- Vectrix VX-1 Li my2011 #3228
- CityEl Fact4 / Mini El Cabrio
- Th!nk PIV4 A266
- Th!nk City A306
- Tesla Model3 AWD
Hello!
Thanks for all the knowledge you all are sharing!
WOndered if this could be a solution to my problem.
I live off grid and do not have a large enough system to charge my VX-1 NiMh through the mains charger
I do not ride it daily, in fact probably weekly is more realistic.
I would love to be able to trickle charge it off the modest solar rig I have (which includes a 1kw inverter)
Ideally I wouldn't bother inverting to AC but have yet to find an alternative solution.
If I made one of these trickle chargers does the assembled knowledge base think it would work?
Thanks
Anthony
Cornwall, UK
Is there anyone in the UK with a .3 amp charger/LED charger?
I'll collect or pay return postage if I can borrow them.
David in Beckenham
Hi i have one if you want to use it I'm in Staffordshire but can post it out to you regards chris
Think I'm sorted now.