Battery pack question

7 replies [Last post]
misfit1
Offline
Joined: 03/11/2012
Points: 7

I have a Vectrix that's been sitting for 2 years. The batts seem like they are now dead. I also live in South Dakota where it gets way below freezing in the winter. Can the batteries survive this or will they freeze and be ruined like a car battery can do? When I plug it in it still does nothing...Thanks in advance for any help.

Comment viewing options

Select your preferred way to display the comments and click "Save settings" to activate your changes.
moccasin
moccasin's picture
Offline
Joined: 07/11/2008
Points: 494
Re: Battery pack question

Your battery is likely fine, but has dropped below the minimum 80 volts required to trigger the charge circuit. It can most likely be put back into service, but you're going to need the assistance of a special charger to bring it up to minimum voltage before you can properly charge it.

While waiting on someone to respond with more specific instructions, you might check the pinned handbook here, as there should be some information about doing that already archived.

fivari
fivari's picture
Offline
Joined: 05/04/2011
Points: 23
Re: Battery pack question

In order to bring the voltage up to the threshold value you could use the self adjusting constant current charger made by a bridgerectifier and an AC capacitor as shown on the Endless-sphere forum. Stay in the neighborhood since the charger keeps on pumping the current in the battery pack until you pack is toasted. All further details are given in the thread above.

__________________

Two e-scooters 1500W 48V 30 Ah LiFePO4

misfit1
Offline
Joined: 03/11/2012
Points: 7
Re: Battery pack question

Thanks for the input guys. I'll definately have to do my homework. I'm not gonna lie..The schematic for the "Freddy Charger" is a lot like the youtube of the Turbo Encabulator to me....LOL
Thanks again,

Anderson
Offline
Joined: 10/11/2008
Points: 134
Re: Battery pack question

Regarding making a Freddy charger; I could make a list of parts and suppliers (USA) if you want.

misfit1
Offline
Joined: 03/11/2012
Points: 7
Re: Battery pack question

If it's not too much trouble Anderson, that would be great!!!
Thanks

Anderson
Offline
Joined: 10/11/2008
Points: 134
Re: Battery pack question

Note I haven't assembled a Freddy charger from the parts I've got yet so I can't answer questions about how it works.

For the run capacitor I got a 7.5 MFD / 440 volt run capacitor like this;

http://www.ebay.com/itm/GE-Genteq-Oval-Run-Capacitor-7-5-uf-MFD-440-volt-vac-50-60-hz-CAP010754O-/370560596413pt=Air_Conditioner...
is rated for 60 cycles (USA).

Notice that of all the 8 MFD run capacitors shown here on E-Bay that have cycle specifications are rated for 50 cycles (european) only.

http://www.ebay.com/sch/i.html?_nkw=8+mfd+run+capacitor&_sacat=0&_odkw=7.5+mfd+run+capacitor&_osacat=0

So I guess the 7.5 MFD capacitor would be the way to go instead of using the 8 MFD one as specified here;
http://visforvoltage.org/forum/7912-nimh-battery-problems-and-cures in post #3

1. One 7.5 MFD / 440 volt run capacitor
http://www.ebay.com/itm/GE-Genteq-Oval-Run-Capacitor-7-5-uf-MFD-440-volt-vac-50-60-hz-CAP010754O-/370560596413?pt=Air_Conditione...
Note this is shipped from the US but if you bought a cheaper one it might be from the far east and end up costing more due to shipping charges.
---------------------------------------------------------------------------------------------------------------------------------------------------------------

There is a special high voltage 1.0 MegOhm ½ watt resister needed unless you use a number of regular smaller OHM resisters wired together in series instead.
That's what I got the Digikey part# 330KH-ND which is a package of 200 330K OHM, ½ watt resisters.
If you download the datasheets you'll find they have a maximum working voltage of 350 which when wired in series of 3 gives you a maximum working voltage of 1050.
Here is a discussion on the subject, see posts #23-26

http://visforvoltage.org/forum/7912-nimh-battery-problems-and-cures?page=2

Note it's important to make sure all the resisters that are wired together have the same resistance, check that by using a digital multimeter.

2. One package of 200 330K OHM, ½ watt resisters to make two high voltage 1.0 MegOhm ½ watt Resistors
http://search.digikey.com/scripts/DkSearch/dksus.dll?lang=en&site=us&KeyWords=330KH-ND&x=12&y=12
---------------------------------------------------------------------------------------------------------------------------------------------------------------

For the 10 Ohm 25 watt Aluminium clad w/w resistor specification there are two that I could find at Digikey

http://search.digikey.com/us/en/products/1625971-5/A102130-ND/2055304 digikey part# A102130-ND

http://search.digikey.com/us/en/products/KAL25FB10R0/KAL25FB10R0-ND/1646182 digikey pat# KAL25FB10R0-ND

3. One of either of the above
---------------------------------------------------------------------------------------------------------------------------------------------------------------
4. Two 100 micro Farads 450 volt working Electrolytic capacitors Digikey p/n P7427-ND -special note these are polarity sensitive
---------------------------------------------------------------------------------------------------------------------------------------------------------------
5. One Bridge Rectifier 600 volt 6 amp Digikey p/n GBPC606-E4/51GI-ND
---------------------------------------------------------------------------------------------------------------------------------------------------------------

6. One 3 amp 1000 volt rectifier (Type 1N5408) Digikey p/n 1N5408DICT-ND
---------------------------------------------------------------------------------------------------------------------------------------------------------------
7. ONE 3.15 AMP Fuse SLOW 440 VOLTS Digikey p/n WK6271-ND
---------------------------------------------------------------------------------------------------------------------------------------------------------------
8. ONE 2.5 AMP Fuse SLOW 440 VOLTS Digikey p/n WK6270-ND
--------------------------------------------------------------------------------------------------------------------------------------------------------------
9. One 150 Volt DC panel meter All Electronics cat# PMD-150V -url is http://www.allelectronics.com
---------------------------------------------------------------------------------------------------------------------------------------------------------------
10.One 3 AMP DC panel meter All Electronics cat# PMD-3A
---------------------------------------------------------------------------------------------------------------------------------------------------------------

Thanks The Laird for the freddy charger concept and help answering my questions.

antiscab
Offline
Joined: 07/07/2007
Points: 1600
Re: Battery pack question

moccasin wrote:

Your battery is likely fine, but has dropped below the minimum 80 volts required to trigger the charge circuit. It can most likely be put back into service, but you're going to need the assistance of a special charger to bring it up to minimum voltage before you can properly charge it.

I agree,

The universal freddy is probably overkill if you are just putting a little in to get the original charger to work

a variac and a rectifier bridge will do

or a rectifier bridge and a light bulb in series to limit current

I would let the original charger do its thing for ~3 hours

then ride it to red battery light
If you don't get far, then bad battery

If you do ok, then check for self discharge

recharge, then wait 2 days, ride, see how far you get
If you don't get at least half bars, you will probably have problems with cell balance due to some cells being held reversed causing high self discharge

Matt

__________________

Daily Ride:
2007 Vectrix, modified with 42 x Thundersky 60Ah
Vectrix 60Ah Lithium Tyres Fuel Registration Insurance cycle analyst replacement TC Charger
conversion
Spent so far: $5800 + $7000 + $1720 + $960 + $320 + $720 + $140 + $600
Cost to do it again: $2500 + $5600 + $1720 + $960 + $320 + $720 + $140 + $600
Cost for a Petrol bike:$6000 + + $1440 + $6000 + $800 + $1400 + $3200 servicing
Total spent: $17260
Total to do again: $12560
Total to have used a petrol bike: $18840
Total distance travelled so far: 79'120km

Comment viewing options

Select your preferred way to display the comments and click "Save settings" to activate your changes.
Customize This