Battery Vehicle Society

badnewswade wrote:Is it not possible to get ping to put two (or even more) batteries together under one BMS? For instance, could he not put two of his 20ah ones together in parallel to make a 40ah one under a high rate BMS so they could both be charged by the same charger?

Hows it actually going BNW, its been a few weeks now and I'm interested on how your finding the Ping pack, are you as pleased with it as I hope you would be ??

ChrisB

I am not ready to buy anything, so I don't want to waste his time with what are at the moment speculative enquiries, just wondered if anyone else was having similar thoughts.

PS I was thinking (and only thinking due to costs) of 40ah on my other electric moped, which is 48v. Would be funny to try it on a pedal-assist though!

EDIT:
Chis, I am very pleased. And I am not easily impressed as you have probably gathered. It sometimes took a little time to warm up but it's totally sound now the pack is broken in and properly wired up. The range problem for my Sakura is now history and so is the AGONY of lugging around lead-acids, and I have the peace of mind of knowing that I'm dealing with a very reputable dude indeed. Pretty sure that it will last until British roads take their toll, quite likely it will outlast the bike it's in.. my calculations show that it could still be in operation ten years from now!

It's a very nice, very stable pack - the only time it failed was in a bad dream!

badnewswade wrote:Chis, I am very pleased. And I am not easily impressed as you have probably gathered. It sometimes took a little time to warm up but it's totally sound now the pack is broken in and properly wired up. The range problem for my Sakura is now history and so is the AGONY of lugging around lead-acids, and I have the peace of mind of knowing that I'm dealing with a very reputable dude indeed. Pretty sure that it will last until British roads take their toll, quite likely it will outlast the bike it's in.. my calculations show that it could still be in operation ten years from now!

It's a very nice, very stable pack - the only time it failed was in a bad dream!

I thought you would be
If you think your not easily impressed you need to try and be me for a day, I'm rarely impressed these days, and even more suspicious of buying in some foreign stuff, did it once before from the US and it was almost the worst thing I ever did and vowed never to try and import stuff again, cost me a packet
But after so many good reviews of Pings stuff I bit the bullet and was equally impressed, the only slight down side was the double sided stuck on BMS, if he could just tidy that bit up I recon they are great and ideal for the plug and play fraternity aka myself

Cant wait to have a play with Eds 36v pack as I wont be quite as scared of it as I am with my 24v pack.

ChrisB

Just my 5p's worth.
I have had a 48v 10ah ping battery pack for 14 months now on my nano brompton, (prob about 15-20 cycles) not used heavily, but it still had close to full capacity when I rode it to cutout a week or two ago. about 9.6 ah on the cycle analyst if I remember correctly. I haven't noticed any drop in performance in cold weather really. Ping also happily replaced a faulty 5a charger when it packed up. Nano goes well on 48v too!

You asked if Ping could put 2 20 Ah packs in parallel to make 40 Ah
In fact he does make 40 Ah packs. To the best of my knowledge the max voltage he does is 48v.
So you could order a 48v 40 Ah pack with a single BMS - if you wish you could specify a high rate BMS that would allow up to 100A discharge ( I have bought exactly this) (though probably drawing this current for for more than brief periods will shorten battery life).

Yeah, I did end up writing to him after all. Costs $1,498 including postage to the UK so I think I'll wait for either a better exchange rate (come on, crazy Republicans! Destroy the economy in order to save it!) or until I have a bit more money. That said it is looking more like a question of when I upgrade rather than if.

EDIT: Do you have an http://www.evalbum.com/page? Be interesting to see what you're running on that chunky BMS.

Personally I plan to go for the standard BMS; according to my calculations I don't need more than 3600 watts to run my 800w motor. (I have a 30 amp fuse for 240v AC, half that for DC and you've got 3600 watts, it hasn't blown in over a year so... I make its drain less than 3600 watts. The standard BMS gives you nearly 4KW to play with - 48V x 40amps at C2 = 80amps - so the standard BMS should just about cover it with some to spare.)

Here's the machine I'm talking about: http://www.evalbum.com/2486

Ah, you're andyw from ElectricMotoring aren't you (and you're "local" to me )? Like you it's now more a case of when I upgrade to lithium than "if" Personally I'm looking to go with Headway cells and have a play with Peter Perkins' BMS - not sure if anyone's used it on a scooter yet!

Oh yeah - Hellos! *waves*

jonathan - are you running your Elcat on that BMS?!

No, the Elcat does not run on the Ping batteries alone. It mainly runs on lead-acid batteries (draws 300 A at full power which would wrech the Pings). The Ping batteries are in parallel to the lead-acids, though can be switched on or off. I use them mainly to boost the lead-acids when resting between journeys.
I'm still working out the optimum way to use them.