DIY stage 2: received Li Ping LifePo4 battery [photos]

[daniel.weck]

Table of Contents:

http://www.pedelecs.co.uk/forum/electric-bicycles/4682-diy-stage-1-received-bafang-tongxin-kits-photos.html#post59183

http://www.pedelecs.co.uk/forum/electric-bicycles/4734-diy-stage-2-received-li-ping-lifepo4-battery-photos.html#post59988

http://www.pedelecs.co.uk/forum/electric-bicycles/4737-diy-stage-3-motor-testing-fork-photos.html#post60039

http://www.pedelecs.co.uk/forum/electric-bicycles/4747-diy-stage-4-16-wheel-lacing-building-photos.html#post60153

http://www.pedelecs.co.uk/forum/electric-bicycles/4769-diy-stage-5-prepping-fitting-electricals-photos.html#post60345

http://www.pedelecs.co.uk/forum/electric-bicycles/4778-diy-stage-6-fork-hub-torque-protection-photos.html#post60504

http://www.pedelecs.co.uk/forum/electric-bicycles/4786-diy-stage-7-first-ride.html#post60641

http://www.pedelecs.co.uk/forum/electric-bicycles/4825-diy-stage-8-continuous-improvements.html#post60991

http://www.pedelecs.co.uk/forum/electric-bicycles/6956-diy-stage-9-a123-nano-battery-pack-photos.html#post88165

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Surprise in the post this morning

36V 10AH V2.5 LiFePO4 Battery Pack

Good packaging, Ping lives up to the expectation so far !

 

[daniel.weck]

I haven't decided yet how I am going to protect the battery on the bike...aluminium casing maybe.
In any case, it'll need to be very waterproof, and of course it'll need to protect the cells from direct shocks.

There are 12 red LEDs on the BMS, to indicate when balancing is taking place (usually after charging). There are in fact 24 cells in this 10Ah pack, but they are wired in parallel pairs, then the 12 pairs are wired in series (2P12S). As each cell delivers 3.2V and 5Ah, this all adds up to 38.4V nominal voltage (3.2x12) and 10Ah. Each cell measures 150x105mm with a depth of 6.25mm, so the full pack is 150mm deep (6.25*24). The thin BMS is very discrete, adding a mere 8mm to the package.

Note: if you ask nicely, Li Ping will build a 5Ah pack at exactly half the depth, using 12 cells in series.

 

[daniel.weck]

The charger is quite noisy due to its built-in fan. At first the fan speed increases gradually and quickly, but then stabilizes to a constant wizz.

The high-quality connector is well worth the price (Hirschmann ST series, 2-way)...but the cables coming from the battery are very thick, so making them fit securely inside the connector required patience, persuasion, and a little bit of blood as well (screw driver slippage into finger) !

 

[monster]

he's using clear shrink wrap on the bms now. thats a nice touch.

 

[jerrysimon]

Another good thread daniel keep them coming. Great for others who are thinking about the same thing.

It looks quite chunky. I wanted a 36v 4 or 5ah one when I was thinking about puting a Tongxin in a lighter bike for my shorter commute.

The guy that posted his site and his kit with the Tongxin and smaller Lithium batteries was the closest I saw, but as you know I ended up with a Cytronex. The smaller NiMh battery is a good compromise for my short commute.

Regards

Jerry

 

[jerrysimon]

Did you get stung for import duty + admin ?

I always seem to get caught

Regards

Jerry

 

[daniel.weck]

3.845 Kg

 

[AndyOfTheSouth]

Yes, good post. As I think Jerry said earlier - no pressure, but we are waiting on each installment!

Inspired by your example, I emailed Ping to ask about smaller and lighter batteries. I received an auto response saying he is on holiday until the 8th.

 

[daniel.weck]

I guess no (nobody asked me to pay anything extra). How would they charge me ? Would the delivery man require an extra payment, or would I be charged on my credit card automatically ??

Did you get stung for import duty + admin ?

I always seem to get caught

Regards

Jerry

 

[daniel.weck]

After less than 2 hours of charging, all the red LEDs came on (balancing time ?):

EDIT: ok, the row of red LEDs is still on, but the charger single LED switched from red to green, and the fan stopped. I guess this is one balancing cycle completed. I will leave the battery to charge until tonight.

Instructions from Li Ping's PDF:

* First charging costs more than 10 hours. Red light turns to green, then turns to red
again after a while, again and again. It’s normal. The charger is balancing the
capacity of battery cells.
* The battery pack’s capacity will be activated to its full capacity after 3 to 5 cycles.
Before being activated, it seems to have 80% to 90% of its full capacity.

 

[jerrysimon]

I guess no (nobody asked me to pay anything extra). How would they charge me ? Would the delivery man require an extra payment, or would I be charged on my credit card automatically ??

Well as its marked gift and below the threshold value that attracts duty you wouldn't be charged lol

When they charge you, you know as it does not get delivered you get a note saying come and collect it and pay £x in duty before it is released. Not only that but they charge you £8 admin fee on top

Well done

Regards

Jerry

 

[Pedalo]

Daniel,
Did you order the battery through Ebay or direct from pingbattery.com ?
Looks much cheaper through pingbattery.com but perhaps there isn't the same level of confidence?

Jerry,
It looks like you went through exactly the same thought process (before you bought the cytronex with MY name on - I'm not too bitter!) as I am going through. I actually want something a bit smaller than the 10Ah ping but probably something a bit bigger than the battery in the freedom kit. I could double up on batteries in the freedom but it's starting to look real expensive compared to sourcing components individually.
I didn't want to spend too much at this stage becuase I'm still trying to gauge what I really want. Also my company is supposedly going to start the cycle to work scheme next year - at which point I'll likely buy a new cytronex!

 

[jerrysimon]

Jerry,
It looks like you went through exactly the same thought process (before you bought the cytronex with MY name on - I'm not too bitter!) as I am going through. I actually want something a bit smaller than the 10Ah ping but probably something a bit bigger than the battery in the freedom kit. I could double up on batteries in the freedom but it's starting to look real expensive compared to sourcing components individually.
I didn't want to spend too much at this stage becuase I'm still trying to gauge what I really want. Also my company is supposedly going to start the cycle to work scheme next year - at which point I'll likely buy a new cytronex!

Yes sounds just like my thoughts.

Sorry about the ebay bike. The whole ebay thing was a bit opportunistic really as I just saw it and thought that is what I am looking for.

We DO have a cycle to work scheme and perhaps if I had been more patient I would have gone with that. Though somehow parking up a £1400 + bike just doesn't feel right in terms of it being nicked. A nice new bike plus the same kit for about what I paid for the Cytronex though sounds like a good idea. Or maybe wait for another Cytronex to come up on ebay. There were two including mine this month that came up. The other one was cheaper and looked in slightly better/ less used condition.

The finish on these things is way above what I could have achieved going down the DIY route. Plus having done one already I didn't really want to face the anxiety of doing it all again should some of the parts not go together well.

Now I can just sit back and watch Daniel

Regards

Jerry

 

[winterdog]

off topic a bit i know but...
is there any news on the increase of the cycle to work amount (2k would be nice)

 

[daniel.weck]

Daniel,
Did you order the battery through Ebay or direct from pingbattery.com ?
Looks much cheaper through pingbattery.com but perhaps there isn't the same level of confidence?

I bought direct from Li Ping's website, and paid with PayPal. So I was not covered by an eBay transaction, and the seller didn't pay any listing fees

I've been lucky with the import duty. Let's see if they charge me for the spokes and nipples from Taiwan ... (they were more than half the price in the UK...so I have plenty of margin)

 

[daniel.weck]

I've just added a couple of photos on the first page of this thread, including a voltmeter showing 41.7V (I usually see 43V just after finishing charging)

I haven't used the battery under load yet, so the capacity is not yet stable anyway. I will monitor charge cycles and my cycling trips in order to gather e-Brompton statistics (I should probably invest in a CycleAnalyst or the cheaper/simpler WattsUp product).

Did I hear "geek" ??

 

[jerrysimon]

No a geek just an enthusiast lol

We are all jealous really, I love tinkering too.

I was like this when I was into Aero modelling. I never did invest in a WattsUp meter though. I have been looking at that cycle analyst as well.

Regards

Jerry

 

[jerrysimon]

Daniel a link for your to look at here

Jerry

 

[daniel.weck]

Thanks Jerry.

I am looking for an aluminium case to protect the battery cells (150mm wide, 105mm deep, 150mm high + 15mm BMS thickness).

I found this:

NEW Hannah Montana CD Storage Case Box Aluminium on eBay (end time 06-Oct-09 10:37:08 BST)



Fortunately, I found a plainer model with similar dimensions, made by Hyundai It was cheap (just under 9 GBP including postage), so if it doesn't work I can always use it for something else ! I should receive it during the week (unless the Royal Mail strikes slow things down...).

Cheers, Dan

 

[jerrysimon]

Lol that one with the design would look great strapped onto your bike. My daughter would love it though she would prefer it if it was all pink.

I think your right to protect it in a case like that and not just chuck it in a panier as some do.

Regards

Jerry