SAFE Recharging of Exotic Batteries, NiMH, LiPO and Complex Battery Packs or Multiple Cells.




About: So what ideas would you like to try?
DO NOT use normal NiCd or Nickle Metal Hydride Battery chargers

Some exotic cells in sizes of 14500 (AA), D and specialized 3.7 to 12v LiPO packs are cheap and easy to obtain but the battery CHARGERS are often difficult to find or VERY expensive. These types of packs and bundled cells are also VERY sensitive to charging rates, temp and current! OR they Explode.

PCB's and special chargers can be had or built from scratch. However free or cheap voltage converters available off the shelf, workbench power supplies are DANGEROUS!

This instruction will show rechargeable battery types, several sizes with codes and nomenclature along with their compatibility with conventional sizes.

Use these in Lights, small toys & Appliances and RC planes and Cars.


Step 1: Exotics - Recharging

Recharging is dangerous take proper precautions:


-never recharge unattended batteries

-charge outside or on fireproof surface (marble/tile/cement)

-Use approve charges that monitor
*current draw

-never use unrated or unknown batteries

-never use more or less cells than charger was designed for!

1) Test cells with Multimeter or rated battery tester, in a pinch use a small LED or lightbulb like a flashlight.

2) Dead cells with ZERO voltage are usually b ad and are to be discarded.

3) THREE or FOUR major battery types are in use
Alakline - these are 'Disposable' like Eveready voltage 1.5v
NiCD/NiMH - 'Re-chargables' reusables usually 1.2v
Zinc Air - One time use when exposed to air, 1.5 to 3v+
Lithium - Polymer packs as below or for 'high drain' devices

4) Specialized rechargers are required for Rechargeable Lithium Polymer packs, these monitor voltages, temp or charge rates. Do not use NiCD or NiMH chargers with lithium packs!

5) Specialized LiPO cells are available in 18650 and 14500 sizes. These can be used in some AA or C cell and larger devices with adaptors.

See my other instructables....

Final notes:

Test positive and negitive poles/tabs with a multimeter. Some "protected" cells have small PCB to control charge/discharge rates and have no "button" tops.

Step 2: Charging!

Some Examples of cells:

Be sure to match charger with cells, current and heat/monitoring PCB's

Reminder: some LiPo cells have 'built-in' charge monitoring PCB's and temp/current cutouts!

The Lt Blue cell below is a AA sized (14500) 3.7v protected Lithium Polymer cell. Great for regulated lights and high power LED or HID bulbs! The Red is a LONG size AA for specialized packs.

Rechargable cells in NiMH for 1/2D size 1.2v can be combined for higher voltages in smaller spaces.

See my flashligh post on instructables.


Step 3: TIPS

Use magnets for connections to button cells.

Charge multiple cells only in rated chargers and in series if charger is rated for multiple voltages.

Lithium cells are EXPLOSIVE if charged in a NiCd or NiMH charger!


Step 4: Custom Work

Some "custom" battery packs...




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    33 Discussions


    Reply 11 years ago on Introduction

    Did ya see step 1? with instructions 1-5?

    The HUGE liPo charger and text w/pic on Step 2 pic 3?

    LiPo Charger


    Reply 11 years ago on Introduction

    instructions here: + to + - to - red to red or red to + black to black or black to - there...


    Reply 11 years ago on Introduction

    Okay, but you missed the bit about "Connect a series ammeter and parallel voltmeter between your lithium cell and adjustable power supply. Adjust the initial voltage so the charging current is about 0.5C, then as current falls off, keep increasing the voltage to maintain current right around there. When the voltage reaches 4.2 volts per cell, don't go any farther, and just watch the current. When the current falls to 0.05C, you're done, disconnect everything and don't charge any more, as trickle-charging a lithium cell will destroy it".

    If that was in the steps somewhere, I must've missed it.

    What's in your steps is roughly "buy a charger and follow its instructions", which doesn't strike me as a terribly useful instructable. That's like posting "how to bake cookies" where the steps are "buy a cookbook" and "follow the recipe". I thought the point if an instructable was to be the recipe, which is why I linked to the Powerstream page when I saw that the details of lithium charging had not been covered.

    I looked as his other instructables - same style - just showing and advocating products that one could buy on the internet.  I believe he is using instructables as a venue to advertise products - or he/she is just a very enthusiastic proponent of such devices/


    Reply 11 years ago on Introduction

    Whoa...bad idea. YES the point here is BUY a Charger for ALL LiPo's or use a LiPo APPROVED PCB Controller. (see pics)....NEVER EVER charge without Current feedback, temp control etc etc... Cells vary by manufacture and come in Button top, Flat Packs and Coil one charge technique does NOT fit all. Danger Will Robinson. YOU go can post that technique and the legal repercussions from the fires...seen the laptop and battery pack fires? These with OEM chargers? Jeez ! LiPo Chargers should never be "simulated" must NOT be a IEEE Member... Only use a rated and approved PCB or Charger for Lithiums. NiMh or NiCd's are simple. There you can monitor voltage and so LiPo's. All add some STEPS for ya... E


    10 years ago on Introduction

    hi ercgillis, want to ask something, I bought a battery pack for my psp and i wanted to add one or two more battery in parallel with the battery inside the battery pack to increase the mAh of the battery pack. is it safe?? or do i need to modify also the circuit? the battery is LiPo.. thanks!!!

    1 reply
    Coffee beanmatse9999

    Reply 10 years ago on Introduction

    u sure mine are lith ion, also check out some the AA charger packs for the psp, i think they would serve better


    11 years ago on Introduction

    My neighbor heard I was building my own battery pack for my bicycle's lighting system and needed a charger. He gave me the old charger to his kid's power wheel. It's 12 volt, but will it recharge a NIMH based pack? I think those power wheels use a lead cell or something like that. Here's a picture of the charger.

    2 replies

    Reply 11 years ago on Introduction

    only use it IF it is specifically rated for NmHy and at the voltage & current max for your pack. The charger fine print will show ... From pic I can see 12v is your bike lite 12


    Reply 11 years ago on Introduction

    Yes. As a matter of fact, I'm rebuilding the pack using 10 NiMh sice C in series. I built it originally with an old rechargable drill pack I had laying around, but now is the time to upgrade I believe. I just need to make sure I have a charger ready for when I do.


    11 years ago on Introduction

    Hey i got that solar pack :D its good if u got the sun for it :3


    11 years ago on Introduction

    nice collection of batteries there!!