Search found 80 matches

by Peter Brigg
Oct 10 2018 9:51pm
Forum: E-Bike General Discussion
Topic: Electric bike has very stiff steering when in motion
Replies: 6
Views: 637

Re: Electric bike has very stiff steering when in motion

Took the headset apart to grease it-the lower bearing was caged and only bit of the cage left-bearing balls missing or chewed up. Surprising that it still turned. A new set of bearings cost $5. They probably won't have a long life as the places where the bearings seated are worn-but one big improvem...
by Peter Brigg
Oct 06 2018 4:42am
Forum: E-Bike General Discussion
Topic: Electric bike has very stiff steering when in motion
Replies: 6
Views: 637

Re: Electric bike has very stiff steering when in motion

Thank you for that information. I sprayed the headset bearings with WD40 and took the bike for a ride-very much improved so i upended it and soaked the bearings with engine oil-now really good. I realise that the oil is not a long term answer and the headset will have to be dismantled and the bearin...
by Peter Brigg
Sep 26 2018 3:22am
Forum: E-Bike General Discussion
Topic: Electric bike has very stiff steering when in motion
Replies: 6
Views: 637

Electric bike has very stiff steering when in motion

I have a 350w electric motor on my front wheel and when under power the bike becomes difficult to steer-more so when I go full throttle. If I reduce power the difficulty decreases-however even then the bike is difficult to steer-not nice to ride on With the bike at rest the front forks are free and ...
by Peter Brigg
Jul 10 2018 11:20pm
Forum: Battery Technology
Topic: New BMS fitted to a 12s LiFePo4 18650 ebike pack
Replies: 11
Views: 685

Re: New BMS fitted to a 12s LiFePo4 18650 ebike pack

Yes-I have one of those chargers for a 12v battery I built as a standby battery for camping-I used 4 of the same cells I used for the bike (Headway 38120). I notice that the charger has a limit of 6 cells so yes-you can use it on half the pack them do the other half The charger also shows the voltag...
by Peter Brigg
Jul 06 2018 5:43pm
Forum: Battery Technology
Topic: New BMS fitted to a 12s LiFePo4 18650 ebike pack
Replies: 11
Views: 685

Re: New BMS fitted to a 12s LiFePo4 18650 ebike pack

Some more information-I supplied the wrong details about the type of cell in the battery- they are Headway 38120 cells-so reasonably good quality. I made the mistake when i made the battery of using a cheap BMS bought on eBay-after some use I was getting only a short ride out of the battery before i...
by Peter Brigg
Jul 06 2018 1:03am
Forum: Battery Technology
Topic: New BMS fitted to a 12s LiFePo4 18650 ebike pack
Replies: 11
Views: 685

Re: New BMS fitted to a 12s LiFePo4 18650 ebike pack

The charger is for a 36v LiFePo4 battery and the voltage measured with the charger on but not connected to the battery is 43.8v

Peter
by Peter Brigg
Jul 06 2018 12:58am
Forum: Battery Technology
Topic: New BMS fitted to a 12s LiFePo4 18650 ebike pack
Replies: 11
Views: 685

Re: New BMS fitted to a 12s LiFePo4 18650 ebike pack

I have some further information to add about this topic. I left the charged battery on the bench overnight (not connected to a charger)and to my surprise the cells had balanced themselves to within a very tight range. They were all within the range of 3.34v to 3.3v. I checked the voltages with 2 dif...
by Peter Brigg
Jul 05 2018 3:24am
Forum: Battery Technology
Topic: New BMS fitted to a 12s LiFePo4 18650 ebike pack
Replies: 11
Views: 685

New BMS fitted to a 12s LiFePo4 18650 ebike pack

Immediately after I charge this pack there is a fairly wide variation in cell voltages-the highest being 3.7v and the lowest 3.3v. I then attach a load consisting of 3 only 12v car taillight bulbs in series drawing approx 2amps and I believe this takes off the surface charge and gives a more reliabl...
by Peter Brigg
May 14 2018 6:55pm
Forum: Battery Technology
Topic: BMS on eBay
Replies: 2
Views: 367

BMS on eBay

I have had problems with BMS on my 12s LiFePo4 electric bike pack and I am looking at buying a bms with this eBay number ( 321048908605 ) The pack is driving a 350w motor so my arithmetic tells me watts divided by voltage equals amps so approximately 10amps is the theoretical figure for the BMS. Pla...
by Peter Brigg
Nov 11 2017 9:39pm
Forum: E-Bike Technical
Topic: Cheap effective BMS
Replies: 1
Views: 344

Cheap effective BMS

I have often used this forum to get info however perhaps now I can contribute something. I have had a lot of trouble with BMS for LiFePo4 12s- and finally decided some time ago to give a cheaper one a try.It has worked well on a 350w electric bike though that may be it's limit-not sure about that. I...
by Peter Brigg
Aug 23 2017 11:18pm
Forum: Battery Technology
Topic: Wiring up a BMS
Replies: 0
Views: 304

Wiring up a BMS

DSC00292[1].JPG I have bought a 12S BMS LiFePo4 and it arrived without any clear instructions for wiring it up. A photo is attached. For some reason the balance connector is split into 2 parts an 8 pin socket and a 4 pin socket. Can someone help me with which cell relates to which pin? Also when wi...
by Peter Brigg
Jul 19 2017 4:18pm
Forum: Battery Technology
Topic: Balancing LiFeP04 cells
Replies: 11
Views: 1271

Re: Balancing LiFeP04 cells

The cells are mainly used-I have 2 batteries and they are now a mixture of cells. One has 10 old and 2 new-the other has 11 old and 1 new. The new cells are Headway-good quality with threaded ends. The original cells seem to be not as good quality as Headways- all spot welded together and difficult ...
by Peter Brigg
Jul 15 2017 2:55am
Forum: Battery Technology
Topic: Balancing LiFeP04 cells
Replies: 11
Views: 1271

Re: Balancing LiFeP04 cells

DSC00258[1].JPG Attached is a photo of how I have setup a method of reading individual cells. I have removed the BMs from this battery and am going to give manual balancing a try for a time. I see now how surface charge can be misleading-after charging the voltage readings are misleading-a load set...
by Peter Brigg
Jul 11 2017 11:23pm
Forum: Battery Technology
Topic: Balancing LiFeP04 cells
Replies: 11
Views: 1271

Re: Balancing LiFeP04 cells

DSC00257[1].JPG DSC00256[1].JPG I thought it I would contribute for a change rather than ask questions. Attached are a few pics-one shows an arrangement on the front forks to prevent the front forks doing a 180 and wrecking the wiring to the front hub. Pretty rough but it works. The other photo sho...
by Peter Brigg
Jul 11 2017 12:28am
Forum: Battery Technology
Topic: 36v battery won't charge
Replies: 21
Views: 1641

Re: 36v battery won't charge

Something more on this 36v electric bike battery-I have 2 of these bikes both with 36v LiFePo4 batteries-they are fairly problem free however things happen. Recently the battery cuts out after using the bike for a short time-eg a 1 km ride. I changed the battery over to the other bike and this confi...
by Peter Brigg
Jul 11 2017 12:17am
Forum: Battery Technology
Topic: Balancing LiFeP04 cells
Replies: 11
Views: 1271

Re: Balancing LiFeP04 cells

All is going well with this 12v battery-the balancing feature works-all cells now sit at 3.32v however I am having difficulty raising the cells to a higher voltage-I would like each cell to be around 3.5v which is around 90% charge. I have bought a Volt 680ac charger which has a few features for LiF...
by Peter Brigg
May 23 2017 3:23am
Forum: Battery Technology
Topic: Balancing LiFeP04 cells
Replies: 11
Views: 1271

Re: Balancing LiFeP04 cells

Thanks for those suggestions-will work through them and come to an answer for sure.
Regards
Peter
by Peter Brigg
May 20 2017 11:31pm
Forum: Battery Technology
Topic: Balancing LiFeP04 cells
Replies: 11
Views: 1271

Balancing LiFeP04 cells

I have made up a 12v battery using Headway 38120 10A cells -a pack of 8 cells with 4 pairs of cells in parallel to make what a charger sees as a 4cell 12v nominal voltage battery. My idea was to have it as a General purpose 12v battery for camping and as an emergency starting battery for a 40 HP Yam...
by Peter Brigg
Jan 25 2017 4:15am
Forum: Battery Technology
Topic: Have built a 12v LiFePo4 battery
Replies: 17
Views: 1499

Re: Have built a 12v LiFePo4 battery

Thanks for that info-yes the individual cells need watching and now I realise that an LVC does not necessarily protect the cells-fortunately all cells are new-no mix and match so that may not be a problem. Re the question of how I get 3v 6v 9v and so on-just by tapping between the cells. Today I bou...
by Peter Brigg
Jan 24 2017 5:01pm
Forum: Battery Technology
Topic: Have built a 12v LiFePo4 battery
Replies: 17
Views: 1499

Re: Have built a 12v LiFePo4 battery

Thanks for those replies-I will ask Dogman Dan a few questions first. With an RC charger-what does RC stand for. And the pack supplies HVC- what does that stand for? I now realise that the battery is set up clumsily-rather than useless outlets for 3v 6v & 9v a simple jst plug is all that is needed t...
by Peter Brigg
Jan 24 2017 12:11am
Forum: Battery Technology
Topic: Have built a 12v LiFePo4 battery
Replies: 17
Views: 1499

Re: Have built a 12v LiFePo4 battery

The Headway cells are 10amp At rest the voltages are 3.37 3.39 3.4 and 3.4 volts When I connect my lead acid battery charger to the battery (briefly) the voltages are 3.68 3.9 3.36 and 3.36 volts. Why would the first 2 cells rise but not the 3rd & 4th? Have incl some photos to help explain. I have p...
by Peter Brigg
Jan 22 2017 5:10pm
Forum: Battery Technology
Topic: Have built a 12v LiFePo4 battery
Replies: 17
Views: 1499

Have built a 12v LiFePo4 battery

I have made a 12v battery using 8 Headway cells configured as 4 parallel units of 2 done up in series to get the 12v. I also bought and installed a low voltage cutout to avoid over discharge. It is boxed up and works well however the 2 pairs closest to 12v+ are now lower than the other 2 pairs and I...
by Peter Brigg
Aug 19 2016 5:32pm
Forum: Battery Technology
Topic: Buying LiFePo4 battery from China
Replies: 7
Views: 843

Buying LiFePo4 battery from China

I have bought 2 only 36v 350W elec bike kits from BMS Battery in China (LiFePo4 type batty) approx 4 years ago-they have given reasonably good service however one battery is now giving trouble-the latest being a dead Headway cell within the battery. I have replaced both BMS's recently-at very reason...
by Peter Brigg
Aug 13 2016 3:11am
Forum: Battery Technology
Topic: No output from battery pack
Replies: 12
Views: 1326

Re: No output from battery pack

Thanks for that -I will give it a go. If I replaced the cell there would be issues about getting an identical cell-I see there are cells of a similar dimension however with greater capacity. Here in Australia the freight is almost the same cost as buying the single cell-not good. What you propose is...
by Peter Brigg
Aug 12 2016 3:28am
Forum: Battery Technology
Topic: No output from battery pack
Replies: 12
Views: 1326

Re: No output from battery pack

A follow up to my earlier posts on this topic-I bought a new BMS and before I fitted it I checked the voltage of each cell in the battery(the battery had been sitting unused for a month) To my surprise one cell was down to 1.8v so I charged it (just that cell only) and bought it up to over 3v When I...