betarambo Posted April 2, 2012 Author Report Share Posted April 2, 2012 I always charge mine individually. If you get it setup in a good way then they are pretty easy to pull out and disconnet. Your setup would be 9S1P when in the bike but you want to charge them individually as 3S1P packs. My normall load now is 2 6S1P 5 AH packs in paralell tied in series to 2 3S1P 5 AH packs to effectively give me 9S2P at 10AH. Even though this is 4 batteries, they fit nicely in the stock battery tray and they are straight forward enough to pull out and charge. It helps that I bought a 250W charger so that I can charge them at 10A (2C for a 5 AH pack) so they generally charge up in half an hour per pack. Quote Link to comment Share on other sites More sharing options...
ninefives Posted April 3, 2012 Report Share Posted April 3, 2012 (edited) Low Voltage Alarms arrived! These are the adjustable voltage type, that simply plug into the balance plug. There is a small button on them that cycles through the alarm voltage setting in 10ths of a volt. I've started off with them at 3.7v They continuously cycle through a very bright display showing overall battery voltage and individual cell voltages whilst plugged in. Feedback on the HK page says individual cell voltages accuracy not the greatest but accurate with overall battery voltage. I have fitted them on 2 of the 10 batteries, but not yet done a field trial! http://www.hobbyking.com/hobbyking/store/__18588__Hobbyking_2_8S_Cell_Checker_with_Low_Voltage_Alarm.html After note. Left the alarms connected. Several days later alarms went off. Cell voltages had become unbalanced 2 at 3.6 and 3 at 4.5 volts!!! both alarms have done this. Now discharging the high cells manually. Got the high cells down but the 3.6 cells will not balance charge beyond 3.8v. I've put in a service email to hobby king but waiting for a response....... Edited April 10, 2012 by NineFives Quote Link to comment Share on other sites More sharing options...
pete_scorpa3 Posted April 11, 2012 Report Share Posted April 11, 2012 I've been following this topic throughout as I have both a 24v and a 36v Osets and battery life is a subject that is important to both my riders. We have a two day event coming up and one set of batteries simply will not do, but there is no mains electricity available at the venue to recharge them. Can anyone tell me what size petrol generator it would need to recharge the standard 12v batteries (one 24v, one 36v) ? Would it be worth doing, or would it be easier to drive back home and charge then overnight, then return the next day? we used to use a 1.5 kva generator for running the road race tyre warmers, but would I need one that big to run the chargers? Pete Quote Link to comment Share on other sites More sharing options...
gwhy Posted April 12, 2012 Report Share Posted April 12, 2012 (edited) I've been following this topic throughout as I have both a 24v and a 36v Osets and battery life is a subject that is important to both my riders. We have a two day event coming up and one set of batteries simply will not do, but there is no mains electricity available at the venue to recharge them. Can anyone tell me what size petrol generator it would need to recharge the standard 12v batteries (one 24v, one 36v) ? Would it be worth doing, or would it be easier to drive back home and charge then overnight, then return the next day? we used to use a 1.5 kva generator for running the road race tyre warmers, but would I need one that big to run the chargers? Pete that really all depends on your chargers, you could get a couple a 12v car battery's to connect your chargers too, you could prob get 2 recharges into 10Ah 24v battery's from a 40ah car battery, deep cycle leisure battery would be better suited. A 1.5kva genny will only put out about 8A so this would do the job but like i say it depends on your chargers. Edited April 12, 2012 by gwhy Quote Link to comment Share on other sites More sharing options...
gwhy Posted April 12, 2012 Report Share Posted April 12, 2012 Low Voltage Alarms arrived! These are the adjustable voltage type, that simply plug into the balance plug. There is a small button on them that cycles through the alarm voltage setting in 10ths of a volt. I've started off with them at 3.7v They continuously cycle through a very bright display showing overall battery voltage and individual cell voltages whilst plugged in. Feedback on the HK page says individual cell voltages accuracy not the greatest but accurate with overall battery voltage. I have fitted them on 2 of the 10 batteries, but not yet done a field trial! http://www.hobbyking...tage_Alarm.html After note. Left the alarms connected. Several days later alarms went off. Cell voltages had become unbalanced 2 at 3.6 and 3 at 4.5 volts!!! both alarms have done this. Now discharging the high cells manually. Got the high cells down but the 3.6 cells will not balance charge beyond 3.8v. I've put in a service email to hobby king but waiting for a response....... You should never leave the alarms connected to the battery's when not in use , what charger are you using ? Quote Link to comment Share on other sites More sharing options...
betarambo Posted April 17, 2012 Author Report Share Posted April 17, 2012 I've been following this topic throughout as I have both a 24v and a 36v Osets and battery life is a subject that is important to both my riders. We have a two day event coming up and one set of batteries simply will not do, but there is no mains electricity available at the venue to recharge them. Can anyone tell me what size petrol generator it would need to recharge the standard 12v batteries (one 24v, one 36v) ? Would it be worth doing, or would it be easier to drive back home and charge then overnight, then return the next day? we used to use a 1.5 kva generator for running the road race tyre warmers, but would I need one that big to run the chargers? Pete Pete, I think you are talking about the standard SLA batteries that the Osets come with, not a LIPO conversion. In that case, the stock 24V charger uses 120 V at 1.2A which is about 150 VA. Assuming the 36V draws a bit more I would say you need maybe 400 VA (.4KVA) to charge both bikes at the same time, which is probably the smallest generator you could find. However, since you need like 8 hours to charge those SLAS this might be a pain. I know it sounds lame, but one option would be to buy an inverter to hook to your car battery. You would need to start the car every so often to keep its battery topped of but at least this way you could use the standard charger without having to get a generator. It is lame because you are going from DC on the car to AC at the inverter back to DC at the battery, but if you have an inverter laying around this would work. I did it this way back before I went to lipos. The better solution of course would be to convert to LIPO so that you could charge in half an hour from your car battery directly. Good luck! Quote Link to comment Share on other sites More sharing options...
pete_scorpa3 Posted April 17, 2012 Report Share Posted April 17, 2012 Thanks very much, that was the info I was looking for. I hadn't really thought the generator idea through, running one for eight hours just to recharge the batteries seems a bit excessive now I think of it. Probably going to be easier to go home, recharge and return the next morning. Thanks again for the info. Pete Quote Link to comment Share on other sites More sharing options...
juanroberts Posted June 4, 2012 Report Share Posted June 4, 2012 We have the 36V Oset. Today was our maiden voyage on LIPOs. We went with two 33V 5800 batteries that in parallel would give 11.6Ah. THE GOOD The bike's increased amperage creates a lot more power, such that there was a lot more wheel spin like on Oliver's videos, and my son Andres was doing a lot more wheelies, and zaps over obstacles. He was flying by himself on a stump he previously would not do if I was not there to catch him, so he gained a lot of confidence from having the extra power (see video below). Although the lead acid batteries we replaced were old, by comparison we did a ride that would have depleted them. Yet each LIPO cell thereafter had used less the half of its voltage (measured 3.95V, where 4.23V is max, and 3.5V is min). The new batteries are probably half the weight as well such that the bike is a lot lighter, even feels like a bicycle, but my son corrected me on that. The BAD Took me a long time to figure the lithium stuff out, I will provide a summary below on what I know now that I did not know when I ordered the batteries. Batteries are fragile, charging is delicate, etc. The UGLY The first charger I used was a cellpro (see listings below). I sent it to HobbyKing but have not heard back. It failed and I went with the one recommended here, the icharger, and even then the balance expansion board it came with had problems (see below). Each order is going to set you back about $75 in shipping from Hong Kong, and the parts listed below alone add up to about $500. I could have saved money by getting a larger number of lower capacity packs, but I wanted to keep it simple at just two. The components that worked: 1x #iCharger1010B/6609 iCharger 1010B+ 300W 10s Balance/Charger = $128.31 1x #9052000014/20968 Hobbyking 60w Power Supply = $9.99 1x #601B-12-10cm/10253 XT60 Female w/ 12AWG Silicon Wire 10cm (5pcs/bag) = $3.85 1x #601A-12-10cm/10254 XT60 Male w/ 12AWG Silicon Wire 10cm (5pcs/bag) = $5.21 1x #LPGUARD25x33/4364 Lithium Polymer Charge Pack 25x33cm JUMBO Sack = $2.73 2x #ZC.5800.9S.25/21386 ZIPPY Compact 5800mAh 9S 25C Lipo Pack = $177.20 1x #601A-2PParal/10265 XT60 Harness for 2 Packs in Parallel (1pc) = $1.97 This one did not work, maybe I was unlucky: 1x #CP10S/14743 Cellpro 10s 260W 10A Balancer/Charger = $114.95 Things to know (I apologize if am repeating previous posts, and all mistakes are mine): *You will need a soldering iron, lots of solder, and shrink wrap. *LIPOs have about 4 volts each, so a 9S = 9 cells, at 4.2 volts each gives you more than 37 volts when fully charged, and 3.5v x 9 = 32 volts when near its lower limit. *A LIPO cell damaged when charged more than 4.2V or drained under 3.5V (this is a conservative static minimum, some go lower as the lower limit is debatable). *Balancing batteries takes time, whereas charging them without the balancing part via only the two main leads is faster. *Balancing a battery is done with the weird multi-colored connectors. If all battery cells are equally charged, there is less risk that one will become overly charged or drained when only using the main black and red leads to fast charge on a later day. *LIPOs do not like to be left fully charged. So when storing them there is an ideal voltage you have to get them to either by riding them, of by using the storage feature on the icharger. *Dropping a LIPO is a good way to damage it and significantly increase the likelihood it will catch fire while charging. I placed a foam pad on the OSET battery tray, and then used the stock cover over the batteries. *The Cellpro charger requires an adapter called a balance expansion board to make it work which I had to buy separate (the icharger comes with this connector already). *The icharger's balance expansion board's second 4S slot had faulty wiring (first two leads were dead, and the other three were off by one, i.e., the one that should be wire #8 was actually #7). I guess jamming the 4S (from a 9S battery) into the second 5S slot which is wired correctly may function as a workaround. Let me know if you spot errors and I will edit them out. Thanks to all that contributed to this thread! Quote Link to comment Share on other sites More sharing options...
gwhy Posted June 4, 2012 Report Share Posted June 4, 2012 All seems good to me, Just a couple of things that could save a bit of money, look for a PSU locally as the weight on the bigger psu's tend to be heavy and expensive to post ( not so much the 60W one above but if buying a 200W+ psu ), its worth sticking with the 5000mA battery's these workout cheaper and are more common, should one 5800mA pack go down it would have to be replaced with the identical capacity other makes may not provide this capacity. The chargers tend to be expensive ( at the moment ) for anything above 6 cells so think about configuring packs using only up to 6 cell battery's the cost of the chargers are so much cheaper i.e $15 for a 150W or $75 for a 400W, a 400W charger will charge/balance a 10Ah 6 cell battery in around 40-60mins ( as long as you have the psu to power it ). And thinking forward if/when oset start using 48v and 70v the 6 cells battery's will be forward compatible as 22.2v blocks. Quote Link to comment Share on other sites More sharing options...
betarambo Posted June 5, 2012 Author Report Share Posted June 5, 2012 One important update for most people who are tackling this for the first time is that soldering is no longer required on the batteries. I found that HK now sells adapters to go from the lame red plastic covered connectors the batteries come with to XT60 so the connector conversion is now much simpler for people who don't solder every day. You still have to do the bike side, but that should be your only soldering. The 9S solution certainly is cleaner and more convenient (I use a 6S in series with a 3S). One counterpoint to that might be the money if a cell goes bad. If a cell goes bad on the 9S the whole battery is junk whereas using a couple of smaller batteries makes a bad cell less expensive. Then again, I am now up to 10 6S batteries and 8 3S and have not had a bad cell at all. I don't need this many batteries, but I bought some extra in preperation for the 20" bike so I could run 15S2P. Speaking of the 20" I officially gave up on waiting for it this weekend. Oset has been on radio silence about when it will actually release. While I can be patient, I can't stop my daughter from growing. She rode her first national a week ago, and this weekend she beat her first "grown up" in a trials. I just can't wait until maybe October or maybe later. This weekend, not only was the 16" getting way too small, but for the first time she didn't have enough power. So I started to build my own. I will start a thread on it and keep you posted. Then again, maybe someone at Oset with see this and decide that they need a pre-production bike in the states for testing! Quote Link to comment Share on other sites More sharing options...
ninefives Posted June 14, 2012 Report Share Posted June 14, 2012 Been a while - just an update. Running 10 x 5S1P 5000ma gives 2.5 times the standard battery capacity of the OSET. Not short of power for about 3 to 4 hours. Batteries hold their voltage well - giving plenty of power - no paddling home with the throttle held open. Upgraded the charger to a dual 400w - what a difference! The 50w chargers were fine for an overnight charge but the 400s give me about a 1 hour charge time total - I don't have a power issue all day, charge off a 12v battery at lunch. My son does the trails with me now. I scrapped the low voltage alarms, they cost me 4 cells in 2 batteries - and no joy with Hobby King for a replacement battery - it became a pointless argument. I have an in-line volt meter - they stop riding when it shows 36v (starts at 42v). Re Balancing - I checked all the batteries after about 6 charges - every cell was identical - apparently charging in parallel keeps them in balance - search the RC forums for the tech info - I just know it's true. Had one issue with a intermittent connection on one of the cells which took out one of the batteries, left me with a bank of 5 batteries and a bank of 4 - the 4 set depleted to a lower voltage 3.3v but came back up no problem. I gently disassembled the faulty battery and resoldered the cell - all good - I did test charge the faulty cell on its own in a safe place. I check all the battery voltages individually now. Now find soldering the XT60s a breeze - a good soldering iron makes all the difference. I'm also at the point of needing a bigger bike - boy turns 9 soon. The OSET goes to the daughter (6) - I have raised the bars with a riser from the cycle shop but we need bigger frame and wheels. The Sherco 80 is just a bit big - alright for riding around the field, but too big for sections. Quote Link to comment Share on other sites More sharing options...
betarambo Posted July 16, 2012 Author Report Share Posted July 16, 2012 I think someone asked about this. I have run my daughter's early Oset (2008) 24V on 36V lipos for a year with no problems. We run 2 6S1P in series with 2 3S1P to get an effective 9S2P for 36V nominal and 10AH. No problems at all. Well, the problem is traction. When things are slick I run her at 6S to keep from spinning. I think her new bike will prevent the spinning... Quote Link to comment Share on other sites More sharing options...
ninefives Posted July 16, 2012 Report Share Posted July 16, 2012 (edited) Interesting thought - does the potentiometer under the seat soften the torque or just the reduce the top end speed? This weekend competed at a ski resort - the OSET blasted up a 500 metre deep dust 1 in 5 (blue!) hill 3 times on the loop, ran most of the day and still had 50% usable battery remaining. Edited July 16, 2012 by ninefives Quote Link to comment Share on other sites More sharing options...
gwhy Posted July 16, 2012 Report Share Posted July 16, 2012 Interesting thought - does the potentiometer under the seat soften the torque or just the reduce the top end speed? This weekend competed at a ski resort - the OSET blasted up a 500 metre deep dust 1 in 5 (blue!) hill 3 times on the loop, ran most of the day and still had 50% usable battery remaining. The pot just limits the top speed. I know that oset have a new controller coming out soon that you will be able to limit the max power and the max speed. Quote Link to comment Share on other sites More sharing options...
reinhardt Posted July 25, 2012 Report Share Posted July 25, 2012 This is a very interesting topic, and are almost more confused than when I've started reading. I dont want to sound lazy, but I am. It seems that ninefives, frogger, gwhy know their stuff?? First of all, the charging seems very cumbersome, ballacing etc, at this moment after riding, plug it in, leave it till the next time, and ride. Do you have to unplug the batteries everytime, and recharge them, balance etc? Can I keep them in the bike for charging? Bottomline, I would like replace both sets of batteries on the OSET 12.5, and 36. I think the 12.5 is 24v? What must I buy where, and what should I do?? Low voltage buzzer? Does the lights indicators on the throttle work, so that stop riding on say 2 lights? Chargers? Batteries? (for both bikes) 2 x 5s1p 8000 mAh batteries, with 2 chargers? for the 36v For the 12.5, 2 Zippy Flightmax 6S1P 15C 5,000 mAH Can you take these batteries on a plane? My Dad is in the UK at this moment. What chargers do I need to charge everything similtaniously? Quote Link to comment Share on other sites More sharing options...
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