I have my Pro Commuter bike and I'm well pleased with it, but the realities of work/weather/general life and my intended use of occasionally bimbling around locally mean that running the (36v 16ah LIon) battery completely flat will take forever in (my) normal use.

Mindfull of the advice that the battery should be conditioned by being completely flattened at least twice for it to give best service I am wondering - how?

If the bike had wired in lights I could simply leave them on, but it hasn't.

I do have an old fashioned caged bulb inspection lamp lying around though and I wonder - if I cut off the plug and carefully jury rig connections to the batteries female connectors will this work? The bulb should glow (however feebly) and so should drain the battery, or am I being naieve? Would I risk damaging the bms? Are there other risks involved? I should add that I am generally safety concious and would do this carefully and with me keeping obs.

Any advice welcome.

Clive.

I have my Pro Commuter bike and I'm well pleased with it, but the realities of work/weather/general life and my intended use of occasionally bimbling around locally mean that running the (36v 16ah LIon) battery completely flat will take forever in (my) normal use.

Mindfull of the advice that the battery should be conditioned by being completely flattened at least twice for it to give best service I am wondering - how?

If the bike had wired in lights I could simply leave them on, but it hasn't.

I do have an old fashioned caged bulb inspection lamp lying around though and I wonder - if I cut off the plug and carefully jury rig connections to the batteries female connectors will this work? The bulb should glow (however feebly) and so should drain the battery, or am I being naieve? Would I risk damaging the bms? Are there other risks involved? I should add that I am generally safety concious and would do this carefully and with me keeping obs.

Any advice welcome.

Clive.

 

You have to dump 576 Wh of energy (36A x 16A). Typically, incandescent bike lights burn about 1 watt, so it will take 576 hours, or 24 days to flatten the battery using the lights alone!

 

I think the safest way to condition the battery is to just go out and ride up and down hills until it is flat. It only need to be done twice, doesn't need to be done in one stint and won't take up a massive amount of time.

what make is a " Pro Commuter bike "

Tillson, the lamp in question is not bike lamp, but an old fashiond 240v mains lamp. As I said the bulb will only glow feebly! Unfortunately 'riding it flat' twice isn't an option, I seek some static means to this end!

Eddieo, Pro Commuter is the brand. Think it might be similar to a Juicy.

Clive.

I have hung my bike from the garage ceiling and jammed the throttle open and left the bike to run itself down. Takes a good few hours as the motor is running without much load.

Lithium batts do not need 'conditioning'!

 

The only point to running it completely down and giving it a full charge is to reset any 'fuel' gauge that may be present in the BMS.

Wish i had your problem flatten my battery 2 times a day with my 40 mile commute. Trek also recommended 2 full discharges but as previously mentioned this was to calibrate the fuel metre.

I think you should also thin about when a manufacture says you get 500 cycles does that include partial charges. From what you say you will be charging from say 75% up to full does this count as a full charge. If that was the case would it not be better to run the battery to 25% and then charge it, just food for thought.

Cycle life is based on full cycle charges, you should get far more part charge cycles. Infact the advise is to charge little and often, you will still be stuck with the natural life of the battery so plan for replacement around the 2~3 year mark.

Tillson, the lamp in question is not bike lamp, but an old fashiond 240v mains lamp. As I said the bulb will only glow feebly! Unfortunately 'riding it flat' twice isn't an option, I seek some static means to this end!

Eddieo, Pro Commuter is the brand. Think it might be similar to a Juicy.

Clive.

 

It's your choice, but I would be hesitant to connect any load to the battery other than the motor via the BMS. zOmb13e might have the best solution to your predicament.

Cycle life is based on full cycle charges, you should get far more part charge cycles. Infact the advise is to charge little and often, you will still be stuck with the natural life of the battery so plan for replacement around the 2~3 year mark.

 

It just does not feel natural, i am so used to charging batterys when they are dead. Glad of the info i find on this forum as i will now charge up more often especially at weekends.

It just does not feel natural, i am so used to charging batterys when they are dead. Glad of the info i find on this forum as i will now charge up more often especially at weekends.

 

I have checked my ProConnect two year old battery. The 10 second test showed 3 lights. This means that the battery is failing after exactly two years and only 384 charges as I charge it every night. (48 weeks x 2 x 4 days = 384 charges)

I don't let it run flat but charged it from two or three lights so that hasn't really extended its life span.

The batteries really are the weak point on these bikes from a financial point of view. Still not bad in the big picture but could be better.

I have checked my ProConnect two year old battery. The 10 second test showed 3 lights. This means that the battery is failing after exactly two years and only 384 charges as I charge it every night. (48 weeks x 2 x 4 days = 384 charges)

I don't let it run flat but charged it from two or three lights so that hasn't really extended its life span.

 

Don't forget to do full conditioning first to ensure your capacity check is accurate.

 

That means riding down to the LED fast flashing empty stage, not just the slow flashing, then a full recharge. I wouldn't be surprised if you then had at least a four LED capacity. It's also important to measure at a comfortable temperature, a cold battery will measure low, so overnight at room temperatures first is advisable for accuracy.

.

I'm confused (frequent problem):

 

I have a new 36v 15ah Lithium Ion battery (duct tape type) on my bike.

 

So far it has only run about 5 times for about 20 minutes each time on average and I have recharged it each time I have returned home. It has never been anywhere near flat.

 

Have I done wrong? Do I need to run it flat a couple of times? This would be contrary to other advice I have received.

 

What's this BMS re-setting thing that's been mentioned.

 

I would really appreciate some concise advice from someone who actually knows as there seems to be some conflict in this thread (no disrespect intended to anyone). Thanks,

 

Dave

Li-ion cells shouldn't be fully discharged. They don't like it. Here comes the but...

 

Most devices that use Li-ion batteries are either charged (and monitored during discharge) by an intelligent circuit that keep the battery within safe limits.

 

All the Li-ion or lithium derivative ebike batteries I have seen have have the circuitry in the battery itself. The circuit serves to ensure the cells are not over charged or discharged and damaged.

 

So to say we discharge a Li-ion battery is true but only as far as the circuity will allow. If you discharged a Li-ion with a BMS and then left it stilling for months it may discharge beyond its design limits and may not take a proper charge after that - though that isn't always the case as I have resurrected laptop batteries that were totally discharged, thought they usually don't last more than a few months after that.

 

The circuitry in the BMS often have led fuel gauges. This is based on maximum and minimum battery voltages that the circuit records over time - how often and when is down to the designer. So the discharge/charge or conditioning cycle is really just to calibrate this gauge and make the lights more representative of the capacity of the battery.

 

The same applies to Li-ion mobile phone battery meters - if you replace an old phone battery, the battery meter is likely to be off kilter for the new battery and letting the phone switch itself off when the battery is low and then charge to full and repeat will reset the meter.

I thought the battery or controller would cut the bike out before damage was done. I find that towards the end of my commute no battery power is showing on the consul just a flashing battery outline but the bike is still assisting but weakly. I immediately put it on charge when i get home or work I do not let it sit about discharged.

It will as pointed out above, when we talk about a full discharge it is to the point where the BMS has cut power....the cells are not at 0 volts, there will be a voltage across them but they will have near zero capacity.

Yet again we have a thread due to concerns over battery life. If the damned things were priced reasonably, no-one would pay too much attention to their lifespan. At the first sign of deterioration, the battery would be replaced. It's only because the manufacturers/importers/sellers all conspire to rip off the consumers that we worry about battery life on ebikes.

 

It doesn't help that their friends on this forum continue to protect them by attempting to justify the indefensible using spurious statistics. I sometimes think that certain members of this forum are in the pocket of certain businessmen as I can't think of any other reason why any electric cycling enthusiast would want to agree with the industry on prices.

 

Indalo

as has already been said lithium batteries do not need " conditioning " in fact running them flat to often can damage them over time. its best to keep them topped up if possible.thats why it cuts out before its compleatly flat by the bms.the only thing that needs to be done with a new battery is to balance it this happens after two of three charges if they are not to far out.youl'l find your phone battery will last a whole lot longer if you keep it topped up rather than wait till its flat before charging.

Edited January 13, 201115 yr by theskip1

Yet again we have a thread due to concerns over battery life. If the damned things were priced reasonably, no-one would pay too much attention to their lifespan. At the first sign of deterioration, the battery would be replaced.

Indalo

 

What a very environmentally friendly way to behave - not.

You are going to replace your battery every 50 cycles are you when the first sign of deterioration occurs? That will be six batteries you will use instead of one. For your ridiculous idea to make economic sense that means a £500 battery would have to magically reduce in price to £75 for you to benefit.

By the way, in your inane little rant you missed out Governments in your tatty little conspiracy theory on everybody being ripped of.

 

I would be a little more inclined to show respect to your ideas if you provided facts and figures to back your ideas, rather than rubbish the figures given by people on this forum who are a lot more knowledgeable than you.

 

Colin

Oh Colin, you really do make me laugh.

 

I hope you feel much better now you've got that off your chest.

 

Indalo

Oh Colin, you really do make me laugh.

 

I hope you feel much better now you've got that off your chest.

 

Indalo

 

It's probably best if we don't indulge inaldo for a while, I think that he is trying to be deliberately provocative with his posting. This forum is likely to be the only place in his life where people react to his existence.

 

He's shown himself to be a bit of a cunning stunt.

Battery cost

 

The lithium polymer 36v 10ah battery on my bike currently costs £270.00. If it only lasts the basic two years it works out at about £0.37/day. I didn't think that was too bad considering the savings I make not using my car so often. Am I missing something here?

I agree in principle with what Indalo is saying: Some replacement batteries seem to cost more than a complete bike with battery from other suppliers. I think you're being unfair criticising his opinions, which to me are valid.

 

If you are handy with a screwdriver and soldering iron, it shouldn't be beyond the realms of most DIYers to re-pack their battery. Even if they don't use a pack that's exactly the same, as long as it fits in the box, it should still be OK. It would be even cheaper if you could use the existing BMS - just replacing the cells. I think there's a business opportunity here that's already starting to be exploited by some enterprising individuals. Also, at some point in the system are two wires that feed the controller with the power - normally 24, 26 or 36 volts. If your battery is duff, there's a fair chance that you can chuck everything upstream and connect a different suitable battery pack into this supply point - as long as you can find a suitable location. This is especially useful if you want to upgrade from NiMHs or lead batteries. These are only ideas to help cash-strapped individuals in these times of austerity. Please don't attempt, if you're not competent.