Ping LiFePO4 & Ezee Quando I

[tom]

Hello,
This is my first post on the Pedelec forum so hello to everyone.
I've just installed a Ping 36v 12Ah LiFePO4 on my Ezee Quando 1. The instructions with the battery stated that it would need to be charged for 10 hours initially. When I put it on the charger it actually only took about 1 hour to do this - mainly turning on and off balancing the cells. I then left the charger turned off and tried it again later and it more or less did the same balancing procedure for about 15 minutes. When I connected the battery to my bike to test it the bike lights worked OK but the controller gave 7 flashes indicating too high a voltage. The voltage across the battery terminals was 44.5 volts. I left the bike lights turned on for about 20 minutes and the battery voltage then dropped below the controller threshold and powered the bike motor normally. I rode the bike into work this this morning and everything worked OK. So I'm just wondering if the over voltage was just a one off, because the battery seemed to be fully charged on arrival from China

Any ideas anyone? Also I should just say that apart from the very basics I'm not that knowledgeable on electrics.

Thks,
Tom

 

[tom]

Update.
Just went out for a 25 minute cycle on the bike over lunch. It would seem that the battery was fully charged on arrival as my impression is that it is still some way from being fully discharged (e.g getting a red light on the battery state indicator on the handle bars). Hopefully the over voltage issue was a one off. I'll know tomorrow morning I guess!

Tom

 

[flecc]

Hi Tom, welcome to the forum. No, that's perfectly normal, the eZee controller accepts from 32 volts to 44 volts nominal, with a typical variation at the high voltage end of plus or minus 0.5 volts. For example my Torq 1 accepts up to 44.4 volts before signalling overvolts, while my Quando II wont accept over 43.6 volts.

It seems as though yours accepts a maximum of just below that 44.5 volts, so you'll either have to cut the charge fractionally short or discharge a tiny bit each time. As the battery ages it may well lose a tiny bit of voltage anyway and self correct.

I'd guess your Ping battery is far too big for the eZee case, so have you got it carrier mounted?
.

 

[tom]

Hello Flecc,
Thanks for the welcome and thanks for the reassuring reply. I guess it will take me a little while to get used to the characteristics of this new battery. I have mounted it in a water proof plastic (food) container on the carrier. I’ve removed the original battery carrier and used a Speakon (rated 20 amp continuous) male/female connector to connect the battery to the bike. I’ve also put a 30 amp blade fuse on the plus side of the battery discharge circuit. I use my bike for commuting (part of which is by train) and never use the carrier as I prefer to use a rug sack for my wet gear. When on the train I prefer to keep the battery in my rug sack as it’s easier to lift/carry/manoeuvre the bike (especially when folded) with the battery out.

Tom

 

[aaannndddyyy]

It’s very important to fully charge a ping lifepo4 completely for the first 6 to 10times, leaving the charger on over night for the first few to balance all the cells, its only necessary to fully discharge the battery once or trice.

 

[flecc]

That sounds neat Tom, and it makes lot of sense with the Quando which has always been a bit heavy for commuting with the battery in place.
.

 

[tom]

It’s very important to fully charge a ping lifepo4 completely for the first 6 to 10times, leaving the charger on over night for the first few to balance all the cells, its only necessary to fully discharge the battery once or trice.

Ok noted.

I did the commute home, bike – train – bike. From the train station to home I let the bike run in scooter mode to discharge the battery further, but it didn’t reach the cut off point although I was getting the yellow light quite a bit.

Anyway I put the battery on charge at 07:00 pm and within a couple of hours there was a steady green light on the charger. I’ve left it on a timer which will turn off at 05:00 am but I don’t think the charger is going to do anymore work tonight. The battery appears to be fuller charged and balanced.
I’m hoping the battery will self discharge a little after that so as to avoid the over voltage problem otherwise I might have to resort to adding in some dummy load as suggested by flecc each morning before I leave. Any ideas on how might do this guys – connect it to 100 watt light bulb or something?

Tom

 

[flecc]

I also use an overvolt battery and for a a discharger have wired in parallel 10 x 220 Ohms 7 Watt resistors I happened to already have, with a suitable connector to take a bit off the voltage. Your 100 Watt mains bulb should discharge it at a similar rate and get you rolling quickly.
.

 

[tom]

Hi Flecc,
I used the bike lights this morning to discharge the battery starting from 45.0 volts. After 20 minutes the voltage was down to 43.6. I think I'll try the discharge idea as suggested. All I need to do is get another male Speakon connector.

Thanks for the help guys.

Best regards,
Tom

 

[tom]

Hi Guys,
Final question…
As I mentioned I use my bike for commuting.
With this 12Ah battery it looks like I’ll be able to do the outbound and return journey on a full charge quite easily (or at least while the battery is in good condition anyway!). As it happens I asked Ping to supply two chargers with the battery – one for work and one for home as I was anticipating having to charge the battery in work for the return journey.

As I’ve got the second charger I’m just wondering would it be best for the battery to give it a top up charge in work each day even though it still has enough capacity to get me home i.e. which is best two half top up charges per day or one full charge per day?

Thks,
Tom

 

[aaannndddyyy]

Hi Guys,
Final question…


As I’ve got the second charger I’m just wondering would it be best for the battery to give it a top up charge in work each day even though it still has enough capacity to get me home i.e. which is best two half top up charges per day or one full charge per day?

Thks,
Tom

Hi Tom my Ping is also a 12 amp V2 (4 amp pouches) but 48 volts. keeping it topped up is better than leaving it run close to empty. I have had mine a few months now after the first 4 charges it dosent seem to need any more balance cycling, I still leave it on over night once every 10 or so charge cycles. Ideally keeping the battery between 40% and 80% charged will give the longest life.
Build the battery into a well padded strong waterproof container, and you should end up with a battery that is reliable, maintenance free and will last up to 10 years.

 

[flecc]

Agreed with Andy, part charges always best with lithium batteries for the longest life. Good thinking on your part getting two chargers.
.

 

[tom]

Hello Flecc & Andy,
Thanks very much for the good advice. I think that’s me pretty much sorted for now.
Again thanks very much for the help.

Tom