09 February, 2015

Repairing and Adflo Speedglas battery ref 837621 with LI-ION 4.2V Cells


Lately I have been repairing multiple wireless devices whose NI-MH batteries have deteriorated ; usually get considerably cheaper make you the battery pack with a new charger is to buy it new; in this tutorial I will show how to build a battery of 4500 mAh 12.6V and 3 packs of 3 cell li-ion parallel each to replace a battery 10.8V and 4000 mAh NI-MH (9 batteries in series 1.2V) with just 32 € (charger not included).
Update: I uploaded how I repair them to youtube:
And slim version.

LITHIUM battery types depending on their composition

The Lithium-ION technology has improved a lot as  the advantages of having no memory effect and higher energy density per kilogram than any other current technology , we can add that  depending on the type of materials used , allows different power / energy densities; we can have instantaneous powers from 1C (2A / time to a cell 2000 mAh) of the LI-Cobalt portable typical 5C of manganese (LiNiMnCoO2) or 15C for the past employed in Automobiles (LiNiCoAlO2) or 30C with LiFePO4 .



In an apparatus for instant high demand as a drill we have to use the Lithium / Manganese (LiNiMnCoO2) or Lithium / Phosphate (LiFePo4) , with somewhat less energy density but more specific power; if we used the usual and economic with high charge density (LiCo) would degrade faster, but can serve if we packs of several in parallel to meet this increased instantaneous demand or limit the power protection circuits (which usually come already in most li-ion batteries sold loose).

Choosing the most appropriate battery configuration

We play with the number of batteries in series got the total voltage , and playing with the number of batteries in parallel to  each cell we get different total capacity and download speed recommended (C) . If we have 6 batteries in parallel in each cell 2A (2000 mAh) each, we 12A in total, giving us if 2C are each a load capacity / safe discharge of 24 Ah.
The famous "C" gives us the maximum download speed correctly and safely in relation to their ability ; if 1C and has 2400 mAh capacity, it says that we can get her 2400 mAh in 1 hour. If 15C outside, could deliver the 2.4A in just 4 "intense" minutes. The lithium / cobalt used in laptop computers have 1C. If we overcome the rate of discharge, sobrecalentaremos the battery and shorten its life (more the faster the download).
With lithium If we do not get a range of voltages with the apparatus in question can run(ranging from 4.2V to 3V discharged fully charged), we can always use the LiFePO4 (with a charger) with a range of 3.2V work charged (to 3.6V fully charged) and 2.5V download limit without significantly degrading.
Note: Total mAh gives us the total capacity of the battery pack in parallel; in this case if we each pack with 3 rechargeable li-ion 4.2V 1500 mAh each, get a pack of 4.2V and 4500 mAh capacity (which is equal to 4.5 amps); if you put three of these packs in series, sums voltages and get 12.6V and 4.5A capacity (assuming all packs are equal).
Repairing the battery

A 3.7 V is not empty, but 20%; 3V will be empty (recommended recharge sooner)

For repair I gained batteries "Trustfire" with a capacity of 1500 mAh with control circuit charge / discharge that prevents the battery charges and discharges above allowed values, and if there is a higher current at 3 amps (possible short), disconnect the battery.

There could be welded directly retaining its circuit board (PCB onwards) batteries, but I preferred to remove it and apply it directly to each pack of three , so that the capacity of each automatically and control is carried per pack of 4 from swinging , 2V which is what interests us.
These control circuits would not be worth if you require more than 2A instant , then have to use other types of batteries (which accept higher current charge / discharge) and different PCBs.
This model batteries feature a plastic and additional positive (as if the PCB is found to have added to their manufacture), so we can start coverage outer shield to be left original blue color and then, raising the plus button, let without PCB:


We proceed welded together by a positive side and negative each other on the other,with thin wire 1.5 mm2. is sufficient (12V 2A) ( here you can calculate the wire size according voltage, amps and longitude), and solder the PCB B- pack to the negative pole and the B + to the positive pole of the pack, leaving the PCB to a side up so that we do not reduce space as space is very limited battery 837,621.


We do the same with three packs , so to put them in series we can only weld the positive of a pack with the negative of the other , given that the two are in the bottom of the box with PCBs above (facing the positive and protecting electrical tape) and going up in the middle to drive aside, because we are also limited in height:

The packs soldiers in series: Positive negative the next PCB
You can see it's a pack of 3 in series with 3 in parallel (3S3P).
Nomenclature: You will see on websites that refer to batteries with formats like "3S6P Lipo" and the like; the S is P series and parallel). Example: 3S2P: 3 packs 2 cells in parallel interconnected in series.

Now we just have to put the packs in place being careful that the poles are well insulated with electrical tape so that there are no shorts .
Caution: A short circuit or overload a battery of this type is dangerous for the large capacity of stored energy per battery; if operated at a temperature above 60 ° C, could ignite . So be very careful when soldering, do not stay more than 30 seconds heating one of the poles to weld !


Only negative would weld the box (brown) to the lower PCB pack and positive (blue) to the positive upper pack and then isolate that there is no danger of short.


The battery repaired

Another example of 3 packs connected in series; one of each pack is different brand but same capacity.
We fix packs with silicone in the corners to avoid dislodging with the punches and fill the holes with plastic bubble for example to restrict its movements. 
We plugged and sealed with duct tape:


We can only get a 12V charger, and between 1 and 2 amps , I recommend either 13V to charge the batteries; thanks to its control circuitry is automatically disconnected after reaching the voltage limit load or discharge (4.2V-2.5V); one of 2A will take to charge 2 hours this pack of 4.5A.
Note: These batteries Speedglas old lead a bleeder resistor and voltage at the pole yellow cable that connects to the fan unit; in case of the low capacity ref. 7.2V 837 620 (6 1.2V batteries in series Ni-MH), carries a very small resistance of 1.5 Kohms SMD, if the value of 10.8V is 5 kohms .

Update 19/01/15: Now I use a more powerful, reliable and that charges equally the different blocks, cell controller chip for 3/4 to 5 Amps available on Aliexpress.


More information:

20 comments :

  1. Please be advised that any field tampering with respirator batteries or other components, beyond maintenance procedures outlined in the manufacturer's user instructions, will void their NIOSH approval, and is a violation of OSHA workplace regulations. For more information, you can contact 3M PSD at 800-243-4630.

    ReplyDelete
    Replies
    1. I think that you are wrong, we are only doing a service maintenance of the battery, not the respirator electronics/components, and the equipment works as before, or even better (providing less inconveniences to the user).
      This equipment is ours, you we do with it all what we want to do. If 3M puts unfair terms for its correct use, I am not worried at all for it.
      It is like when you loose the guarantee in the equipment if you use another compatible battery... it is certainly an abuse.

      Delete
    2. if 3m didnt absolutely over charge for batteries, people wouldnt have to find work arounds to fix/repair their batteries.. $400 for $30 in parts is madness..

      Delete
    3. Agreed. there prices way to high

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  2. Have you tried to messure How much actual adflo respirator draw amps to run?
    on the market there are many different pcb with various amp same lithium batteries different amp 6/10/15/20/25 which on is ideal to run? If the adaptor run at 2.5amp max, is it worth to use pcb and batteries more than 6amp?
    My other question is -- confusing yellow cable, where do you solder to?

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    Replies
    1. When the filter is very dirty, it can go as high as 3 amperes, so you can use a 4 or 5A PCB.
      The yellow cable is very important for the equipment to detect correctly the battery, and is connected to the negative pole with a 10K resistance in between. A charger of 1 or 2A is recommended.
      I have repaired a lot of this batteries with excellent results; obtaining 8,7Amps of capacity (more than 2 days of use) and a durability more than 5 years (the container last less than the battery itself XD ).

      Delete
  3. Estoy en ello ,he intentado comprar 2 baterías de litio nuevas por eBay desde Inglaterra por unos 130 euros cada una pero sin éxito de compra y me he aburrido,me he puesto a arreglar las mías de una manera distinta ,he comprado 6 celdas de 5A cada una 3,6v y haré dos paquetes ,tengo una batería vieja de litio la cual he destripado ,tiene un circuito controlador en su interior y he comprado un cargador de segunda mano con el que cargar correctamente las baterías ,la idea es hacer las pruebas pertinentes y luego hacer dos paquetes de tres celdas igual al que trae encapsulado en epoxi y colocarlos en el cinturón llevando sus cuatro cables a la caja de la batería la cual llevará un conmutador para elegir que batería quiero cargar o descargar dejando la caja de la batería antigua fija .

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  4. I would like to modifie my adflo so it wouldn't turn off when the filter is glogged. Any ideas how to do it?

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    Replies
    1. The only way to maximize the life of the filter, is to shake it when it is exhausted one or two times max, and to have the battery as full as possible. Other options are unhealthy.

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  5. Basically when you use both filters, dust and gas, then even if the filters are new it still would show that filter are glogged. 3M didnt think that through. Im tired of turning it on every time

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  6. Hi there, I would like to perform this rebuild. Would you mind if I reached out to you for some help or perhaps a walk through of this?? I have 3 of these batteries that a rotate on a charger daily and recently one of them died so now I was trying to get my employer to replace them but it's not looking too good lol. My email is: gman1181@gmail.com

    ReplyDelete
    Replies
    1. Dear welder, I can send you photos of the repairing actually, but it is better a video, so I am going to upload a video to youtube as soon as possible. Regards, David

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    2. Hi David,

      Have you had a chance to upload your video yet?

      Thanks

      Charlie

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    3. Dear Charlie, still without time for that, but I will do it sooner than later. Regards

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    4. Here you can find the video I uploaded to Youtube:
      https://youtu.be/yK40fq0yoII
      And slim version:
      https://youtu.be/6fV7MQjEu3w

      Delete
  7. I replaced my newer black colored adflo with older gray one and it wont shut off anymore - was the newer version broken or different by designe.
    I usually buy hd batterys from private persons, for the last one i paid like 70 eur. If you are from EU then use olx.pl - there is alot of adflo stuff for half the price

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  8. good morning i have a similar problem.
    i have a black adflo without battery, i built a battery with 3s 2 p lipo samsung cell, 12.8v 5800 mah.
    when i connect the adflo battery turns on by pressing on but then the filter status is not seen, and by fading off it does not turn off.
    I can only increase the speed by holding down the on button and lower it by holding down off
    greetings Nicola

    ReplyDelete
    Replies
    1. I repair a lot of them nowadays, you can find here how I do it, on Youtube:
      https://youtu.be/yK40fq0yoII
      And slim version:
      https://youtu.be/6fV7MQjEu3w

      Delete
  9. hello, while I was removing the charger from the battery, the socket at the end of the charging cable was broken. Where can I find this socket?

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