Best Charger For $$

[meatwad99si]

yep its turned on. I was using 4v and 4 amps I think. Its an issue with the 306b not just me. Plenty of other guys with the issue. It even ask me to confirm it before it starts discharging and I hit yes. I'll prob rig up some lights and see how that works. I rarely need to use it and it gets hot but still discharges.

[Skidpad]

Originally Posted by meatwad99si

yep its turned on. I was using 4v and 4 amps I think. Its an issue with the 306b not just me. Plenty of other guys with the issue. It even ask me to confirm it before it starts discharging and I hit yes. I'll prob rig up some lights and see how that works. I rarely need to use it and it gets hot but still discharges.

You have to set the voltage higher than your regen destination, ie, I use a 12v lead acid battery, so my regen settings are 14v and amps correspond to how many batteries I have connected.

If the voltage is set too low, it will use the standard resistive discharge instead; it's in the manual for the 206b at the end of the section where it explains each mode...may be in a similar place for your 306.

[Talesin]

Skidpad's got it right. iCharger 306B manual, page 11, point 5, bottom of the page:

5．If input power supply voltage is more than setting regenerative limit voltage, charger will not start
regenerative discharge and internal discharge instead.

Meaning if your input (car battery) voltage is higher than the regen voltage is set to, it'll just heat-discharge instead. Looks like that's your (and others') problem... and why it's getting so hot. Bump it up to 14-16v regen discharge (multimeter your battery, or figure out the max safe charging voltage for it) and see what happens.

Could also be why the manufacturers weren't too concerned about fixing it... if it was working as intended.

[meatwad99si]

wow i feel dumb, but hey atleast now i know, ill share what happens!

[jperkosk]

Originally Posted by mtuccio

A 1C charge rate on a 2200mAh battery is 2.2A. If you are charging at 13.2A then you are charging at a 6C charge rate...

Not when he's charging 6 packs in parallel

[mtuccio]

Missed the "six" part of the post......

Thank you all for correctinbg me on this.

I never parallel charge biggger packs because I've seen bad things happen when doing this not to mention that it is very important to have balanced packs when using a multi-pack setup such as in the 600EFL or the 700E.

[RedOctobyr]

What kinds of bad things? You mean like accidentally plugging a charged and discharged pack together, and melting/burning something? Do you avoid parallel charging "even" 3S 2200 batteries?

[Natewin]

I recently picked up one of these Thunder 1220 chargers.
So far it seems pretty good. You get 20A output for under $90 shipped.
It doesn't have as many features as the iChargers like temp probe / data output but it does offer 12s charging.
It will show individual cells while charging. It will also show IR of each cell and the entire pack.

[jperkosk]

A proper parallel charging will not allow current to flow from one battery to another, in fact it's quite safe to charge as many batteries as you want in parallel, different capacities and different state of discharge. Two firm requirements:

• You have to use a proper parallel charging board
• All batteries have to be the exact same S count, can't mix 3S and 6S, for example

[mtuccio]

Originally Posted by RedOctobyr

What kinds of bad things? You mean like accidentally plugging a charged and discharged pack together, and melting/burning something? Do you avoid parallel charging "even" 3S 2200 batteries?

What you have decribed is one thing that I have seen happen before and that scenario is not pretty. Cell to cell voltages also vary from pack to pack when used and this can cause imbalance to grow as packs are used frequently. Since parallel charging doesn't understand idividual cell information the charger can be sending current to places that really don't need it and cell imbalances will result. Not a huge effect but something that's not very good for the life of the packs in the long haul. If you run a 14s cabable charge system like I do then you can charge four 3s packs at a 4C charge rate and keep in full balance during the charge with the proper stuff. This can give you 4 chraged 3s packs in about 10-12 minutes which will yield 16+ minutes of flying time (without cool off periods) so my charging setup exceeds what I can fly so no need to consider parallel charging in general. Even with only two battery setups for a 550E and a 700E at the setup will charge a battery faster then I could fly and let the heli cool down. Sinces batteries are a huge cost in this hobby, I'm going to be darn sure to protect my investment and do everything that I can to keep things running in tip top shape....

[FailureToFly]

If you do 'parallel balance charging' (say six 2200 3S batteries) doesn't this 'roughly' charge the packs then balance each individual cell at the end? This is what I thought happened though I'm fairly new to this charging setup.

If doesn't or it's not accurate etc, I'll then periodically do an individual balance charge on all the batteries to keep them balanced.

[RedOctobyr]

Originally Posted by jperkosk

A proper parallel charging will not allow current to flow from one battery to another, in fact it's quite safe to charge as many batteries as you want in parallel, different capacities and different state of discharge.

Forgive me, but are you sure that's true? Items in parallel *can* have current flow between them. And they *will* flow current very quickly if you have a big difference in voltage (eg- a charged battery and a discharged battery connected in parallel). Items in parallel, by definition, will equalize with each other. Now, I've heard people say that, for instance, a 0.1V difference between parallel-charging batteries is OK (I'm thinking of 1S examples). They don't have to be *exactly* the same, but they should be close (to avoid damage to the batteries and wiring), or at least that's my understanding.

Originally Posted by mtuccio

What you have decribed is one thing that I have seen happen before and that scenario is not pretty. Cell to cell voltages also vary from pack to pack when used and this can cause imbalance to grow as packs are used frequently. Since parallel charging doesn't understand idividual cell information the charger can be sending current to places that really don't need it and cell imbalances will result.

If you only connected the main discharge leads in parallel, I could see how you could get cells out of balance (varying from cell-to-cell). But if you also connect the balance leads to a parallel-charging board, in addition to the main discharge leads, wouldn't that give the charger the ability to balance the individual cells of all the packs? Connecting the balance leads to a parallel board, even if you didn't actually do a Balance Charge on the charger, would still electrically connect all of the balance leads. So the different cells of the batteries would equalize with *each other* (even if you didn't actually charge them at all). So all the cell 1's might be 4.17V, cell 2's at 4.21V, cell 3's at 4.18V, if you don't Balance Charge. If you do an actual Balance Charge, wouldn't that let the charger bring them all to 4.20V?

Also, on the note of burning something up by connecting a charged to a discharged. I'd never thought about it before, but if your batteries never charged at more than, say 5A, maybe you could help protect yourself. You could, if you wanted, make custom charge leads, to go between the main leads of the batteries, and your parallel charging board, and put an inline fuse on each one. Say, a 10A fuse, if you never charged at more than 5A. It would not interfere in normal use. But the one time you goof and connect a fully charged battery in parallel with the discharged ones, you'd blow the fuse on the wire leading to the charged battery.

Sinces batteries are a huge cost in this hobby, I'm going to be darn sure to protect my investment and do everything that I can to keep things running in tip top shape....

Amen to that My little mCP X batteries say they can be charged at 3C or whatever, but doing them in parallel, I have just done everything at 1C so far. I plan to try and do my 450 batteries the same way.

[mtuccio]

Originally Posted by RedOctobyr

Forgive me, but are you sure that's true? Items in parallel *can* have current flow between them. And they *will* flow current very quickly if you have a big difference in voltage (eg- a charged battery and a discharged battery connected in parallel). Items in parallel, by definition, will equalize with each other. Now, I've heard people say that, for instance, a 0.1V difference between parallel-charging batteries is OK (I'm thinking of 1S examples). They don't have to be *exactly* the same, but they should be close (to avoid damage to the batteries and wiring), or at least that's my understanding.



If you only connected the main discharge leads in parallel, I could see how you could get cells out of balance (varying from cell-to-cell). But if you also connect the balance leads to a parallel-charging board, in addition to the main discharge leads, wouldn't that give the charger the ability to balance the individual cells of all the packs? Connecting the balance leads to a parallel board, even if you didn't actually do a Balance Charge on the charger, would still electrically connect all of the balance leads. So the different cells of the batteries would equalize with *each other* (even if you didn't actually charge them at all). So all the cell 1's might be 4.17V, cell 2's at 4.21V, cell 3's at 4.18V, if you don't Balance Charge. If you do an actual Balance Charge, wouldn't that let the charger bring them all to 4.20V?

Also, on the note of burning something up by connecting a charged to a discharged. I'd never thought about it before, but if your batteries never charged at more than, say 5A, maybe you could help protect yourself. You could, if you wanted, make custom charge leads, to go between the main leads of the batteries, and your parallel charging board, and put an inline fuse on each one. Say, a 10A fuse, if you never charged at more than 5A. It would not interfere in normal use. But the one time you goof and connect a fully charged battery in parallel with the discharged ones, you'd blow the fuse on the wire leading to the charged battery.

Amen to that My little mCP X batteries say they can be charged at 3C or whatever, but doing them in parallel, I have just done everything at 1C so far. I plan to try and do my 450 batteries the same way.

I should have been more clear in my post and clarified if using a balance board or not. Most incidents I've heard of and seen happen were from setups that did not utilize balance boards so thank you for pointing this out...

In regards to the balancing it will eventually balance the cells but some chargers actually take quite sometime to finish a pack once they get close to a near fully charged pack (my hyperions charger is a good example). The more packs you have in the charge could lead to longer charge times depending on cell imbalances. The hyperions reduce the current way down as the reach the end of a charge and throwing the last 5% into the pack can sometimes take longer then the entire charge to get there did. How long this takes will really depend on how good the batteries are that you a running and how balanced they remain after a run.


Interesting idea on the fuse...In theory this should work as you describe and would warrant some further investigation through practice....Good one....

Peace...

[jperkosk]

Originally Posted by RedOctobyr

Forgive me, but are you sure that's true? Items in parallel *can* have current flow between them. And they *will* flow current very quickly if you have a big difference in voltage (eg- a charged battery and a discharged battery connected in parallel). Items in parallel, by definition, will equalize with each other. Now, I've heard people say that, for instance, a 0.1V difference between parallel-charging batteries is OK (I'm thinking of 1S examples). They don't have to be *exactly* the same, but they should be close (to avoid damage to the batteries and wiring), or at least that's my understanding.

You're right of course, if the batteries are hardwired directly in parallel, but I wasn't talking about this scenario, it's dangerous, for the reasons you've described. A proper parallel charging board will have a diode for each battery which will prevent a current flow between the batteries. A decent charger also detects a total connected mAh automatically by measuring internal resistance, so the batteries that are discharged more will get charged first at whatever rate you've preset. Then as the voltage raises the charger will detect more batteries "coming online" and will automatically increase the current to maintain the preset charge rate. At the end of the cycle the cells are balanced, exactly the same way as with a single battery. First cell of 3S 2200mAh pack will be treated as 3.7V 13200mAh cell if you are charging 6 packs in parallel.
So again, the only limitations for safe parallel charging are:

• decent charger with a proper parallel charging board
• all batteries need to be the same S count (they can be in all different states of discharge, though, no problem)

[RedOctobyr]

Interesting. My apologies if I'd misunderstood how typical parallel charging boards are set up. I've only used parallel charging cables so far (1S batteries, everything hardwired together), and am just getting a board, for 3S use.

I wasn't aware a typical parallel board had any sort of means of preventing current flow between batteries. I thought they simply had all the same connectors wired together (main + together, etc). At risk of perhaps showing my ignorance, how does that work? I could see how a diode could maybe be used to control the direction of current flow, to prevent one battery (at 4.0V, say, for 1S) from discharging into another battery (at 3.9V, say). Or, phrased differently, to try and ensure that current can only flow into the battery, not from it. I'm not an EE, so I'm thinking of the diode as simply acting as a checkvalve for current (using the classic water analogy). But how would it work for discharging, then? If you made it so battery A could not feed into battery B, would that not also make it difficult to discharge with the parallel board? Sorry if I'm just not getting it

[jperkosk]

You're getting it perfectly, RO

A diode is a check valve for current. Not clear on how discharging can be accomplished with a parallel board, or even if it's possible If possible, suspect it's not done through the main discharge cables but rather through a balance connector, with some means of limiting current from each cell, a resistor or maybe even a switching transistor? I could be wrong, though, and there could be a on-board transistor bypassing the diode (like a override valve in parallel to the check valve), but I'd be very careful here, everything will depend on how the parallel board is designed.

Should be getting my PL6 with a parallel board in a couple of weeks, will test, possibly even read the manual

[lovespicyfood]

Good info, thanks!

[mtuccio]

The only thing I'm going to say to all of you reading this is BE SAFE at whatever you do in regards to parallel charging. There are good chargers on the market that will do this well and there are some that I wouldn't trust doing this at all. More importantly make sure that you buy good supporting hardware and that it has all the required electrical hardware needed to protect your batteies and avoid potential disaster. It's hard enough to deal with a LiPo fire from a single battery going up in smoke on the bench during charging so keep this in mind when you are planning on hooking 6 of them up together. I personally wouldn't recommend that you do this inside you house on a work bench even if you are standing right next to it because you aren't going to be able to deal with 6 burning batteries if there is an incident. Use your head, use LiPo sacks, think about everything you are doing, and remember that LiPo fires can happen even when things are done right. If you have never had to deal with a LiPo fire then good for you but don't take the attitude "it will never happen to me". I've seen it happen at the field and in shops by people that have tons of experience so it does happen.

[wagspe208]

So, after reading posts I CAN parallel several 3S 2200 MaH packs even if the starting voltage is slightly different. Or I can hook up 4 packs with a balance board like the one from progressive rc 2 newer packs and 2 older ones and all will be cool??
Thanks
Wags

[jperkosk]

No to the first one. The voltage would have to be almost identical for you to hardwire several 3S batteries in parallel safely without using a parallel charging board.

Yes to the second one, as long as all batteries are the same S count, can't mix 3S and 2S for example.