Connecting Batteries in Series - Charging 12V Lithium Batteries

📖 My best-selling book on Amazon: cleversolarpow...
🎁 Free diagrams: cleversolarpow...
In this video, I will talk about connecting batteries in series. With a focus on 12V lithium batteries in series, charging 12V batteries in series, and the overall concept of series batteries.
We start with the basics: understanding how connecting batteries in series can increase your system's voltage while keeping capacity the same. Imagine taking two 12V 100Ah batteries and wiring them into a single 24V 100Ah battery.
But what about the power? Does it remain unchanged whether you choose series or parallel wiring? I'll break down the math, showing that the total power remains constant, and how this understanding can guide your system's configuration for maximum efficiency.
The video has practical advice, distilled into three rules for connecting batteries in series to avoid common pitfalls, such as mixing different capacities or chemistries, and the importance of charging your batteries before a series connection.
But there's more to it than just the how-to. I delve into the pros and cons, highlighting the advantages like cost savings on wiring and charge controllers due to increased voltage, reduced voltage drop, and more efficient power distribution. Yet, the story wouldn't be complete without addressing the potential downsides, such as the challenges of battery imbalance and the need for voltage converters for your 12V appliances.
Through diagrams, and wiring examples, from the simple 2S configuration to more complex setups like 4S2P, I explain how to design and optimize your battery system. Whether you're looking to build a 24V or 48V system, this video has you covered, offering insights into balancing, charging, and the critical role of battery management systems (BMS) and lead-acid batteries.
As we explore the intricate dance of connecting batteries in series, my goal is to help decrease the cost of your off-grid solar power system without compromising on performance. From selecting the right batteries and chargers to understanding the nuances of series vs. parallel connections, this video is for anyone looking to enhance their off-grid solar setup.

[@stephenhickman9502]

I'm ordering a paperback copy. Thank you brother

[@cleversolarpower]

I appreciate your support! If you have questions feel free to email me.

[@jlplumley2]

This is helping me so much. Thank you for making these videos.

[@elliottsmithlove1]

Thank you

[@davebruessow6842]

Now wishing I'd have jumped straight to 48 volts instead of buying a second 12 volt battery (trust me, I thought about it). Good tutorial and I agree with you...

[@cleversolarpower]

We all learn. Hopefully your system isn't large already.

[@davebruessow6842]

@@cleversolarpower not at all (it's very small). Amazon was gracious enough to allow me to return the second battery (this morning), so now I can move forward with what I really want to do...;-)

[@andrewdemus]

me too😢

[@cypotony2619]

Very clear lesson

[@brushbum7508]

Good Evening ! Just got your book last week. TAKE CARE..

[@cleversolarpower]

Thanks!

[@jimsgarlat7328]

Thank you for the video. Very helpful. I have a 4s4p 12.8v 51.2V LFP system. These are new batteries. Like you say in your video I am concerned with balancing. A video on setting up a balancer would be useful to me and others who bought 16 batteries! I don't believe my system is optimized and would like to get it better balanced. Would adding bus bars help? The batteries are wired correctly. Thanks in advance for your thoughts.

[@cleversolarpower]

Check out my video about wiring batteries in parallel as well. For a series connection you can just use the wires, or you have to make custom busbars which might not we worth it. For the parallel connection i would use busbars.

[@SonorityVideo]

Hi Nick, I just received your book it's very informative and will be very useful for putting up my 5kw system. I just would like to know the best way to wire together 6, 25.6 100ah batteries. I want, for now, to run them through my Bluetti that has a maximum voltage of 145. It would be terrific if you could do a video on how to safely add batteries to Bluetti type generators so as not to have to buy their very expensive expansion batteries. Keep up the great work. Carlos.

[@cleversolarpower]

Thank you for getting the book. I think you mean 145V max solar input voltage, not battery voltage. I don't have experience with adding extra batteries to the bluetti. I think they have a limited charging power from a DC source, so it wouldn't be ideal. It's better to build your own solar generator where you can add components to your liking.

[@SonorityVideo]

Hey, thanks for replying so quickly. You are right, of course. It's just that I knew nothing when I bought the bluetti and now I know much more, with your help. Do you have details on how to build your own solar generator because I could probably be able to sell the bluetti and would love to build my own. Thanks again for your help. Carlos.

[@marcvandaele1878]

Good video about building a good system If you build a 16s2p(or 2p16s…what’s the difference?) with 304AH and top balance them before can you suspect that they gone stay balanced in long run with a active balancer on the BMS

[@cleversolarpower]

Its a big difference. the first means you have two separate packs of 16 cells in series (i recommend this) and the second one is two cells in parallel and then series connected with another two cells in parallel, and so on. i do not recommend the second option. Why? in the first option every cell has it's voltage sensor from the BMS, in the second you have one voltage sensing wire for two cells. I would not top balance, they will balance over time with the BMS (if you have active balancing).

[@dustydawson8977]

Absolutely awsum video, I do have a question/scenario. In a system set up in a solar generator where the batteries stack one on top of the other, wouldn't this make the top battery take more load than the others,and if so,how to get around that,just rotate the batteries bottom to top every so often.I ask because most manufacturers are using this setup. Point Zero Energy(titan) Eco Flow Ultra,and so on,is this the only answer, to rotate and rebalance each battery individually?

[@cleversolarpower]

They are connected in parallel, not series. Check my video about connecting batteries in parallel.

[@stevewhite9813]

Your the man thanks for sharing 👍

[@cleversolarpower]

My pleasure.

[@williamconroy5910]

Question, I have 2 - 12V LFP batteries connected in series and will use them to connect to a Pecron solar generator via the solar input to charge it during emergencies. When I drain the batteries, I have a 20 A - 12-24V charger to recharge them. To recharge, do I connect the alligator clips to each batteries terminals to charge them separately while they are still connected in series or do I attach the alligator clips to the load terminals, + on one battery and the - on the other battery? Great videos BTW.

[@konkaragounakis5924]

Excellent presentation Nick, clear and concise. How and where can i by your book shown in this show? 🇦🇺

[@cleversolarpower]

You can get it on any amazon store if you search for: 'off grid solar power simplified' or if you want a pdf version, you can get it on my website.

[@konkaragounakis5924]

@@cleversolarpower thanks I'll order the book.

[@kangkaiTV]

Thanks brother

[@MegilUrgand]

I want to connect 2 same type 12v LiPo batteries in series to give a 24v arrangement. You stated each battery must be individually charged before connecting them. Can you explain exactly how I would do that and what parameters should be used to determine the batteries are sufficiently charged so they can be connected. I am looking for a practical “how to” explanation. Thank you.

[@simonpatcharinvenaglia7892]

Charge them on a Lithium charger till there full, the charger will stop charging at that point. That's all I do.

[@raymondconnor9808]

I have 10 24v 2.2 kw 67ah 8s NMC lithium batteries. I would like to configure them into a 2s 5p connection as per your 2s 3p diagram, arriving at a 48v output. Should I use one 8s BMS per battery or one 48v 16s BMS per two batteries? Please give me your thoughts on this setup and any suggestions. Thank you!

[@evrenforest2578]

Hi, thanks for the informative videos. I purchased 8 deep cycle gel batteries 4 months ago. I ve had no time to install them. I keep them in a cool place. Probably they ll be stored 1or 1.5 months more. Will this storing ruin the batteries? Thanks.

[@cleversolarpower]

A few months will not have an effect. Charge them before storage.

[@kestrel-68-36]

If a 24v LFP 100Ah has a discharge rate C1 of 100A but I want to use a 3000w inverter I understand that I will have a load of 125A. When adding 2 or 3 more batteries in parallel to make a 24v 200-300Ah can these 2-3 batteries theoretically output 300A? And question #2 In the same example using 3000w 24v battery the cables/wires connecting batteries together should be rated for the Max system loads eg. 125A or 100A that is the maximum battery charge/discharge rating?

[@cleversolarpower]

A 24V 100Ah battery at 1C can output a power 100A*24V=2400W max. Yes, if you have more batteries in parallel, you will increase it's current deliverability. The cables should be rated for the max current draw from the inverter, not the battery. If you expand your battery, the cables are still correctly sized.

[@dandgerousdave4308]

great video do you have anything on bms size and how to work out whats needed for 24v and 12v /

[@cleversolarpower]

I don't. However, I will add it to the list of topics to cover in a video. 12V needs a 4S BMS, while 24V needs an 8S if you use LiFePO4. The C-rate of the cell should be more than the rating of the BMS. Example: 4 280Ah cells is series makes a 12.8V battery with a max C-rate of 280A. Use a 12V 100A BMS and you can draw a max of: 12V*100A=1200W from the battery.

[@jorgeoliveira4152]

Hi, I have a 24v -200a/h system, using 4 lithium 100a/h, So, serie and parallel with a solar panel of 460w. After about 4 months working,the system went down. I checked everything, and on the serie system, one of the batteries still showing 13v and the other around 8v. , on both of the systems.I suppose that if they go down, they go both down, isn't it? Many thanks, if you can help me with this.

[@cleversolarpower]

Did you connect the main positive and negative opposite of each other as shown in the video? Take out your batteries and charge them individually. Then connect them again in 2S2P. If need be, install a balancer between the 2 series connected batteries. email me if problems still persist.

[@alantierney1]

With lithium ion batteries, why did they say you can’t hook more than four up in series? I would like to hook up 6 to make 72v

[@cleversolarpower]

The BMS has components that cannot go over 60V (mosfets) so if you connect them in series the electronics will get damaged.

[@michaelmello9510]

Great video

[@MrTroubleshooting]

Can you guide about 36v system and battries in 36v

[@cleversolarpower]

It's the same setup as these diagrams. For 36V, you need 3 batteries in series.

[@rlikemoney]

So off topic sorta, I have a small bluetooth receiver I use for my car, and battery life on it is short, and I have a bunch of disposable e cigs with lithium batteries, can I solder extra batteries from the disposable vapes to the battery in the bluetooth device to increase battery life? My concern was about charging, will they charge the same? Or one more charged than the other?

[@cleversolarpower]

The vape batteries will be their own battery pack with BMS. A guy recently made a video about it where he got the salvaged vapes and made a battery pack out of it. Searching for diy salvaged. vape battery pack will get you to it.

[@rlikemoney]

@cleversolarpower thanks dude! Was it a video from big Clive by chance?

[@Duckybhainewsfeed]

Can u make graph for me 12v 13 batteries 48v witing

[@1GREATDANE]

Can I Have 4 12 Volt Batteries Seried in 2 Packs for a 24 Volt System to Buss Bars for Charging n Inverting without using a Battery Balancer ?

[@cleversolarpower]

Yes, bit over time imbalances will occur. You either need to recharge the batteries individually or get a balancer.

[@a64738]

Problem is that 24V LifePo4 cost double of 12v batteries (with same A/h), same problem with 48v.

[@cleversolarpower]

It's not a problem. You are paying for more capacity. A 12V 100ah battery contains 1280Wh, while a 24V 100Ah battery contains 2560wh.

[@sun-sea-solar]

If you had 4 x 230 watt panels and 2 x 410 watt panels in a 24v hybrid inverter. What would your advice on wiring them in.? The mppt takes 60v to 500v

[@cleversolarpower]

Checkout my video about wiring mismatched solar panels. You need to know the vmp and imp of the panels as well.

[@sun-sea-solar]

@@cleversolarpower I have all that information. I'll take a look at your video. The 4 x 230 are old poly panels and they 2 x 410 are modern DAH half cell panels. Much higher Voc on those

[@sun-sea-solar]

@@cleversolarpower DAH 410 vmp 37.5 imp 10.5 and the Trina 230 are vmp 29.5 imp 7.78

[@sun-sea-solar]

@@cleversolarpower I did the 2 Dah panels in parallel. The 4 x Trina panels in series. Then both sets in parallel

[@cleversolarpower]

The best solution would be to have the four panels go to the MPPT and the two others on a separate MPPT. Now you are losing power.

[@daved6284]

Hi i have 2 rechargeable lithium 1.t batteries in a device that are connected in series, but the charger for the device is no longer available, it has a barrel connector to charge the batteries, can I use a 4 battery lion as charger connected to the output of one of those outputs to a barrel connector to charge these 2 batteries? Otherwise I have to take the device apart, thanks

[@daved6284]

I can use nimh batteries but I still need to know how to charge the 2 in series with one single input, thanks

[@cleversolarpower]

I'm not sure about that. Check the voltage of the charger and the charging voltage of the battery you want to charge.

[@darioking3133]

Top top top!!!

[@cleversolarpower]

Not wrong, take a second look 😉. 2 batteries in series, in three parallel strings. 2S3P.

[@shmellyhandsprod]

STUFFING MY KAYAK WITH 3 12V LiFeP0⁴ 100AH IN SERIES TO MAKE 36V OK NOW CAN I BUY 3 MORE DO THE SAME IN SERIES THEN PUT BOTH SYSTEMS TOGETHER IN PARALLEL TO INCREASE AH TO 200 AH 36V BANK🤔🧐 TRYING TO RUN A 3.0 HP stern motor on my kayak? AND NEVER RUN OUT OF BATTERY 🤙🏽🤙🏽🙏🏽

[@gemar649]

where do i wire it for charging

[@cleversolarpower]

Same place as the discharging.

[@judenoukui550]

How can I buy one of your book?

[@cleversolarpower]

Yes, it's in the description of the video.

[@jte_polnam]

can buy pdf files

[@rodolphealmaguer8711]

You are not explaining how to balance manually two batteries that need to be hooked in series.

[@cleversolarpower]

Check the video again, I say that you have to charge the batteries to the same SOC.

[@rodolphealmaguer8711]

@@cleversolarpower Found a new video that explained it in details. Thanks.

[@javiercoronel1169]

Make your own video clown

[@dominus6695]

Twelefold haha

[@user-dc2ot2tj2b]

200 year old knowhow like electricity and they think they are experts.

[@9092295772]

Excellent 🎉