Search found 401 matches
- Sun Jan 23, 2011 12:01 pm
- Forum: All things battery related
- Topic: Li-poly batteries - incendiary device look out!!
- Replies: 8
- Views: 21166
Re: Li-poly batteries - incendiary device look out!!
The whole LiPo fireball myth has been elevated to almost cult status, now, it seems. I spent some time trying to track down and separate genuine lithium battery fire cases from mythical ones to see just how probable it was that these cells would catch fire in normal use. The first thing I discovered...
- Sat Jan 22, 2011 2:30 pm
- Forum: All things battery related
- Topic: Ping Batteries in cold weather
- Replies: 49
- Views: 106250
Re: Ping Batteries in cold weather
Connecting Ping packs in series can blow the BMS if one pack of the two shuts down because of a low cell condition or because of over-current. Connecting them in parallel is OK, but best done with a couple of low voltage drop diodes, either Schottky diodes of a suitable voltage and current rating, o...
- Mon Jan 17, 2011 9:58 am
- Forum: Events
- Topic: Land's End to John o'Groats EV Challenge
- Replies: 11
- Views: 29606
Re: Land's End to John o'Groats EV Challenge
Ballast to be a 70kg inertia flywheel that is spun up to silly thousands of revs by means as a braking device, which is then engaged to drive the vehicle when moving off from a stop, or when ascending a steep hill :) Deker :roll: It worked OK for flywheel powered buses (http://en.wikipedia.org/wiki...
- Sun Jan 09, 2011 9:10 am
- Forum: All things battery related
- Topic: Working out battery internal resistance.
- Replies: 5
- Views: 14946
Re: Working out battery internal resistance.
Not that wise, I'm afraid, and not that old either (although I am now retired.........). This method isn't super accurate, as it doesn't take true account of the effect of pulling pulsed power from the battery (to do that needs a measurement with a super-imposed AC component) but it's good enough fo...
- Sat Jan 08, 2011 12:09 pm
- Forum: All things battery related
- Topic: Working out battery internal resistance.
- Replies: 5
- Views: 14946
Re: Working out battery internal resistance.
If you can measure the current flowing from the battery and the battery terminal voltage (right at the battery terminals) then that is all you need to work it out. Here's the procedure: Connect an accurate voltmeter directly to the battery terminals and an accurate ammeter in series with battery pow...
- Fri Jan 07, 2011 9:29 pm
- Forum: All things battery related
- Topic: Super capacitors anyone?
- Replies: 6
- Views: 37741
Re: Super capacitors anyone?
Yes they are far, far, bigger and heavier than batteries of the same energy storage capacity. Self discharge is comparable to batteries. They are for sale because they are now readily available, but they aren't a substitute for a battery, by any stretch. Their advantages are that they have a very hi...
- Fri Jan 07, 2011 5:32 pm
- Forum: All things battery related
- Topic: My new ping- lights on BMS not working
- Replies: 15
- Views: 36723
Re: My new ping- lights on BMS not working
Woah! Chill dude! I have two bikes. The one I'm talking about is this: http://www.evalbum.com/1370" onclick="window.open(this.href);return false; It's the Sakura s200, which uses 36v 15ah batteries to power a 200w motor, and I have indeed replaced like for like. Just got a reply from Ping - it migh...
- Fri Jan 07, 2011 5:29 pm
- Forum: Hybrid's Corner
- Topic: Contactor-based Power Assist
- Replies: 10
- Views: 64500
Re: Contactor-based Power Assist
By pure chance, someone's just posted the spec for the original Briggs and Stratton Etek motor on the ES forum. As I thought, the rpm limit is fairly low. Here's a cut and paste of the spec: 12 HP Peak, 2.7 HP continuous Voltage........................50 VDC Max Nonload Current.....6 AMP Max Nonload...
- Thu Jan 06, 2011 7:33 pm
- Forum: All things battery related
- Topic: My new ping- lights on BMS not working
- Replies: 15
- Views: 36723
Re: My new ping- lights on BMS not working
That's odd. Have you replaced like with like in terms of usable capacity, current delivery capability and voltage? As I recall your bike was running on 48V SLAs of 28Ah, plus an additional pack of 48V 20Ah, giving you a total of 48V, 48Ah. I believe that you've now decided to replace this massive ba...
- Thu Jan 06, 2011 9:58 am
- Forum: All things battery related
- Topic: My new ping- lights on BMS not working
- Replies: 15
- Views: 36723
Re: My new ping- lights on BMS not working
Yes, that's normal. The LEDs will gradually turn off as the surface charge bleeds off and the cells all equalise.
Jeremy
Jeremy