hi
4 battery * 3 in parallel
is there a way to charge it easily?
i would like if it’s possible to connect only the + and - of the whole …
thank
The battery is 14.4 volt if LiIon or 4.8 volt if NiMH.
Terminal voltage (end of charge) on the lithium is 16.8 volts. You need to run a power supply /charger at or under under the terminal voltage.
this kind of charger should be ok
http://www.jameco.com/webapp/wcs/stores/servlet/Product_10001_10001_2151478\_–1
Either use a hobby charger or don’t do it. You should have balance taps.
Not safe! Some cells could be at 4.1 volts or less at end of charge and the rest will be at 4.3 volts or more. Must use balance connector for series as wight suggests!
12 battery 18650
3.6V nominal
4.2V charging
i created this with the link wight have provided
http://picpaste.com/parallel_serial-SOrk8DCl.jpg
i don’t know if i need to find a charger who will be able to charge 3 block of cell or 12….
i only find charger for 6 cell like this one
http://www.hobbyking.com/…/\_*7028*\_Turnigy_Accucel_6_50W_6A_Balancer_Charger_w_accessories.html
It sounds like you need someone to step in and spell this out. That someone is not me, sorry.
You need to use a hobby charger, the Accucel 6 you linked to is an inexpensive / cheap example of one. It’s probably fine, but it’s not high end. (I do not use a high end hobby charger myself. I use an inexpensive one.)
On the link I provided, please turn on “Show Balancer wire hookup? (?)”.
Here are a couple of links. I have not fully reviewed them.
- Battery balancing - Wikipedia
- A Guide to Understanding LiPo Batteries — Roger's Hobby Center (see the section titled “Proper Care & Treatment: Charging”)
You’ll want 4.2 volts applied to each set of three. And triple the recommended single cell charge current.
Don’t you want a charger that uses AC? The one you picked is for out at field R/C use (12 volt DC). Try this:
You also need a balance connector. I think one of these. Cut connector off one end and solder to each set of parallel cells. Go to rcgroups or similar forum for more detailed instructions.
do schema connection is only for the charger?
so i will need to do like this
top connector is for the charger,
bottom one for the light
In my opinion you do not have enough experience or knowledge to custom build your first pack. I recommend that you purchase a pre-built LiPo pack as well as a hobby charger. Once you have more experience you might decide to start building custom packs.
Here is one option: ZIPPY Flightmax 8000mAh 4S1P 30C - this type of battery comes with an appropriate balance lead for inexpensive Chinese balance chargers.
If your budget allows I recommend that you purchase ThunderPower instead, along with an appropriate charging setup. (At a minimum you’ll need a balancing harness adapter to charge on a cheap charger, or just get a ThunderPower charger.)
in my opinion too, but i need to start somewhere.
That’s correct but there’s always only one black. All others might be red and have a positive potential.
The Zippys mentioned are good, inexpensive batteries and LiPos are more practical as a pack. Personally, I’d only run primaries in series whenever possible. When sub-Cs were popular, I’d start with an 8S and a month later, it’d be down to a 4S as I’d remove and discard cells that got reversed charged. Without matching, balancing and constant low voltage monitoring, lithiums pose a bigger danger.
if it’s easier to do it all in serie, i will choose this way, but surely in term of charging i will need to manage all the balancing….
i just want to be able to use a cree xhp70 around 3000lumens during 4 hours.
so i could use 10 x 18650 or 8 x 22650, but that will be hard i think to fine a driver who will support that and anyway
the pack need to find in a cylinder of 7cm of diameter
if i use only protected battery, do i need to have a pcb
when i saw the price of this battery… i motivated to create mine.
http://shop.kecodiving.be/?product=34ah-111v-li-ion-battery-pack-2
battery pack seem to use a normal charger for this battery
http://shop.kecodiving.be/?product=34ah-battery-pack
You are currently a long way from understanding this. I think that you also have trouble understanding English (at least in the context of these systems) based on your response to lightme.
Do you have dive experience? Do you know anyone who knows anything about any of this stuff?
You need guidance. This is not a dive forum, we only have a few users who use dive lights. Elsewhere there is good information about custom built dive lights.
I understand that you may be a beginner, but you’re a beginner trying to build a dive light from scratch. Do you already have a good primary and secondary dive light?
The pack you linked to is 34Ah, which is much higher than what you are talking about building (betwee 6Ah and 15Ah). It’s also lower voltage. Very different!!!
As I recommended earlier, for this application you want to _purchase a pre-built pack.* There is nothing stopping you from purchasing a pre-built pack which fits where you need it to. You do not need to spend 650 Euros.
Once you learn more about batteries, LEDs, driver circuitry, etc…. then come back to building packs. You’ll almost certainly decide that you don’t want to build your own. It’s not worthwhile. I’m a long time user of batteries, I’ve built my own packs multiple times. It’s not common for pack-building to be worth it for the end user.
All good advice above
But isn’t there an easier safer way without needing balance circuits, protection systems ? If someone is determined to build their own battery packs
I’ve pulled a few battery packs from high drain devices (handheld Dyson vacuums spring to mind)
They use from what I can find out, 18650 Sony cells (imr maybe) and green in colour.
In the Dyson for example, there are 6 cells in series giving just over 21 volts, there is no balancing leads or protection circuitry, just a simple charge through the feed +&- the only nod to any sort of safety is a temperature probe in the middle of the pack that cuts the power if it overheats
Would cells like that not be ideal for a novice looking to build a pack?
You can still buy the cells, I looked last year as I had a couple of packs I want to recell, not a huge amount of info on the net about them and what I found was a few years old from when 18650 cells were hard to come by, but the info I did find said they didn’t need balancing and we’re a very safe chemistry
if i want to build from scratch a dive live, it’s surely because i dive.
i have made before but only with existing piece, now i want to do more
very different, but use the same battery 18650.
surely 3S10P, pack don’t seem to big
just don’t understand why there is only 2 cables, don’t seem to have any plug to be able to balance
All you need to understand is that you must balance. If you’re looking for different advice you’ll rarely find it here, or on CPF, or any other internet forum which concerns itself with Lithium Ion rechargeable cells.
“Self balancing” is a real thing where certain chemistries are able to burn off excess energy as heat and by overcharging a pack you can get it to balance on it’s own. I consider this an advanced topic.
I recommend considering “self balancing” cells insurance until you have the knowledge and experience to fully understand what you might be doing. Balance balance balance.
marc.collin, the pack you linked to for 650 Euros includes a BMS (battery management system) circuit. This circuit protects the pack against shorts, overdischarge, and overcharge. It also most likely handles balancing. Laptop computer battery packs function in a similar way, although they normally have a more complex BMS. The Panasonic cells they use are certainly not self balancing, they require management.
Batteries with more parallel cells and less series cells are less likely to get very far out of balance during cycles (assuming each parallel set has a roughly equal mix of unmatched, healthy cells). But they’ll still go out of balance. You could get away with series charging for a while but as the weaker cells get more deeply discharged with each cycle, they’ll eventually fail. If only one cell shorts internally, the remaining, healthy cells will receive a charge voltage well over 5 volts!
Batteries with more series cells and less parallel cells are more likely to get way out of balance and the cells can be even more easily destroyed.
I learned my lesson with safer NiCads so if you’re considering any kind of series configuration of secondary cells, get a safe, premade pack with factory matched cells and hobby charger/balancer. Lithiums aren’t as forgiving. Balance charging and monitoring is the only way to keep series cells healthy and safe.
Seems to go against the grain, but with the correct cells, it doesn’t seem to be an issue or too difficult to safely build a pack that doesn’t need a snakes wedding of balance leads, Dyson and a many others seem to do it without issue , you just need the correct cells and a thermistor, we see people on here do far more difficult and technical things all the time
There’s plenty of info out there on it if you hunt for it and far safer than people just strapping old laptop pulls together and hoping, which is what we often see.
so if someone’s asking for advice we should really try and give then all the information, we shouldn’t avoid giving bits of it just because is not the norm or we think it’s too advanced for them