should I buy a hobby charger?

One has to look at what their current and future charging requirements are and choose a power supply accordingly. I would suggest choosing a power supply with more power capacity (wattage) than needed since most of us always underestimate what we really need. This would also ensure you were set for all future charging needs.

LapTop power supplies would be under powered for my needs since they are under 100 watt.

Good Information Here on choosing a charger and Power Supply:
http://www.tjinguytech.com/charging-how-tos/wattage-for-charging
http://www.tjinguytech.com/charging-how-tos/shopping
Converting PC Power Supply
http://www.tjinguytech.com/my-projects/convert-pc-ps

Bill

It is very hard to overpower a laptop power supply charging 18650’s since you will be charging them in 1S parallel and most chargers max out around ~10A of current that means the max wattage it would need is less then 50W.

My laptop power bricks vary between 65w and 90w which is more then enough.

Oh my old laptop PSUs are all 120W
Gaming laptops of course

For the 50 and 80W hobby chargers a not gaming laptop PSU is strong enough

For those 300W chargers a good 500W PC power supply should be fine, they should deliver 300W 12V

I Balance charge all my 18650 cells. This requires that they be charged in series. Works well for my needs.
Bill

You should really consider going with a parallel charging setup.

Basically balance charging allows you to balance (duh) a battery pack that is made up of multiple cells in series and can not be separated.

Since we have access to each cell individually with 18650’s it is far better, quicker, and easier to simply charge them in parallel. This also ensures they are 100% balanced along with being way faster.

Balance charging will charge the cells up pretty quick at first but if the cells are not pretty close to balanced to start out with it can take many many hours to balance them as I am sure you have noticed. This is because it has to charge them up until the highest voltage cell is at 4.2V (usually a bit over that which is not good). Once that happens it stops charging and starts discharging the high voltage cell until it drops down to ~4.15v or so.

It then charges the entire pack again until that high cell once again reaches 4.2V. It then repeats this process until the pack is “balanced. Needles to say this is VERY inefficiency, wasteful and far from ideal method to charge cells and very time consuming. The only reason it is done is because in RC battery packs for example you can not separate the cells for individual charging so this is the best they can do.

Parallel charging on the other hand charges all the cells evenly through the entire charge process and balances them perfectly the entire time. It also reaches peak charge and stops charging, reducing wear and tear on the cells. Every discharge/charge cycle eats a bit of the total battery life, even the small ones from balance charging.

In a nut shell, if you are using a hobby charger to charge 18650’s, charge them in parallel. You will save a ton of time and it is better for the batteries.

As you can see earlier in this thread, I have a bank of 14 cell holders for mass charging 14 cells in parallel. Now at 5A charge rate it is a bit slow but still a whole lot faster then charging them with a balance charger. Plus if I want to go faster I will hook it up to my 15A DPS5015 and charge them that way, I rarely need to do that though since I have a lot of spare cells.

I have thought about getting a second Imax B6 and either setting them up in parallel or with separate charging banks to allow them to charge things faster. It still works out a lot cheaper then a 10A charger and I could add a 3rd for way less then a 15A charger.

Yes, it’s brand new so not much info on it yet. A bit more risky than and SC-608, but this company seems to know what they are doing so if you want to be a bit adventurous go for the new model and if it works out you get nice benefits… if not well you have to buy something else. The SC-608 will be less expensive and remember you may want to buy a power supply for the charger unless you have something you plan to rig up. They can be a bit pricy for a nice one.

Go slow. Maybe don’t try to do everything at once. Definitely for your Battery Pack salvage usage this is not what you want, but it sounds like you understand that.

is it really that you cant adjust end voltage with SC-608, cant find information, if so its lost opportunity. i have b6 mini and with that you can adjust anything.

but why is it that there is no good banks or holders available, i want couple spring loaded 4 bay holders which way i could charge 26650 through 18350 or so with hobby charger.

SC 608 has options for 4.2, 4.1, 4.35, and LiFe.

A Review of the 608 vs 620 in German, so you had to use Google translate

The sc608 can be had for 42$ with the linker cable if vip2. I can get the price down with points. Q6 will be around $60 with the cable. Except for more power what is the difference between the 2? The 208 can do 8A charge current so that s 8 cellls charging at 1A each or doesn’t it work like that? This would fit my needs, I m still looking into the q6.

Also: if i want to charge 18V packs will I need a ps that gives 18v or can i still hook it up to a 12v battery? I have zero knowledge bout charging packs.

Yes the price of the 608 is better. Basically the Q6 is more power capability in about the same amount of space, but different layout. If 608 has enough capabilities then sticking with that one will save some good money. The 608 was on for around $33 with coupon at one time, you might want to check ebay i think it was around $36 there. For a hobby charger you need a power-supply that can provide the slightly more than the total amperage required, and slightly more than the total charge voltage so for 8 batteries that would be 8x4.2V or 8x4.3V if you still want to charge to them in series. Parallel i think you understand, but that is risky with salvaged batteries. Even serial is risky unless they came from the same pack or measure very close in capacity and Ri.

An 18/18.5V Li-Ion pac is 5S so 20-21V fully charged. You'll need a 22-24V power supply to charge them depending on the charger which may have some series diodes for protection and cable and other losses. Update... Sorry for the miss information. It will depend on the charger, but it seems all the newer ones will boost the input voltage as required, as long as the input power supply can deliver the required power (wattage) that will be required on the output. I don't use big packs, but I see my B6-mini has no problem with 6S packs with a 12V input. My power supply is well above requirements at over 360Watts @ 12V.

I don't have my Q6 yet, it will be another week or two.

Thanks man.
€33 for the charger then u have to spend another 7for the linker cable, comes out about the same…

To clarify, are you referring to the B6 or the B6 “mini”? They are different

I think it was B6 didn’t know there’s a mini….

Sorry I gave you very incorrect information. Depending on your charger you will be able to charge your 8S packs with a lower input voltage. The SC-608 though is only good for 6S packs. I update the original post.

The linker cable is not really necessary. I have a linker cable and I haven’t updated the firmware at all.
The most recent updates only change some slight things like clicker sound and added some European language support.

If you want to charge an 18v pack at 8A you will need to make sure your power supply can put out 150w. Most laptop powersupplies that you may find for free are usually 65w.
I just bought a 150w gaming laptop charging brick for $6 on ebay.

I just realized something. If I wanne charge cells in parallel do they all have to have the same capacity and be dis-charged to the same voltage/capacity? Obviouly my cells won’t be discharged to the same level as I use em in single cell aplications. So I’m guessing a hobby charger won’t fit my needs probably.
Aaaaah f*#@ I really haven’t tought this thing through.

edit: for those intrested gb has a nice deal on the iSDT sc608

No, but the chargers list in the specs the maximum current over the balance port, so if the cells are very different it could take a long time while they wait to get slowly balanced by the balance port (at like 200mA or something extremely slow like that).

That’s not true don’t balance when parallel charging.
The cells will self balance.

Oh I didn’t see that part, I thought he was series charging them.
Parallel charging cells that are at very different capacities is bad because a lot of current can flow from one battery to another if the voltage delta is large enough, which can cause the cells to heat up or potentially explode.