Earlier this month, we wrote about the new Bosch 18V 6-port charger, GAL18V6-8. We asked for clarification about its 2-stage charging behavior, and I wrote more about that here.
Bosch said:
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When four of the 5 LEDs light up, this indicates that the battery in that bay is charged to approximately 80%. The user can then take the battery out of the bay for use and doesn’t have to wait for the top off cycle to finish.
I interpreted this to mean that, with multiple batteries on the charger, you need to watch for the LEDs to indicate 80% charge capacity, which is the approximate cut-off where fast charging switches off to slow top-off charging.
Fast-charging to 80% and then a slow top-off charge seems like a convenience.
Then, a reader suggested that we got it wrong – Bosch’s charger worked much differently than the impression we were given.
We asked Bosch for clarification, asking more specific questions about how the charger works. This is what they said:
The charger will finish the first cycle of charging at 80% and move counter clockwise to the next battery until each battery on the charger has reached 80%.
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The charger will then circle back around and top off each battery to 100% for a second cycle of charging.
The LED indicators are necessary as they show the current status of each battery. This feature allows the user to visually see what stage of the charging phase each battery is in. For example, 1 light indicates 20% charge, 2 lights indicates 40% and so on.
What if you need to recharge several batteries, and you want one particular battery charged to 100%? I guess you could charge one battery and then connect the others to the charger, or maybe find a second charger for that lone battery. Or, if you want long enough, all of the batteries should charge to 100%.
I still think this could have been an opportunity for Bosch’s “Connected” system, but that probably would have just driven up the cost for the benefit of few users.
Charging all batteries to 80% and then all to 100% seems like a convenient feature, and helps to make up for this being a sequential charger. As a sequential charger, it can only charge one battery at a time.
This is a nice touch, that in my opinion makes the charger quite a bit more appealing.
Price: $99
Toolfreak
Given how the customers this is aimed at will probably wind up using it, the 80% initial fast charge seems ok, since it gives you enough charge to keep working while the next battery is charging up to 80%, too. It probably won’t keep up if you have more than one person and all are using high-drain tools that eat a battery faster than the charger can, well, charge.
Seems like it’d be ok for someone who brings in a 6-pack of discharged batteries at the end of the day and puts them all on, then the fast/slow charging cycle lets the batteries cool down before getting a slow charge to 100%.
I still like having individual chargers rather than depending on one charger for multiple batteries, but this seems like a good deal for $99 from Bosch.
andy
Each user is different, but I can say that this would definitely keep up with my team of 3 remodelers on just about any job.
Randy
This seems like a well thought out design. The only functionality I wish they had included was a stereo radio with Bluetooth. Then, I could listen to the radio while the batteries are charging and not have two separate devices. Missed opportunity.
King duck
Wish the Milwaukee was like this and honestly pulling the battery at 80% is probably pretty good for the health of the battery. I thought I would use my sequential charger more but truth is with all the chargers I ended up with from kits I have plenty of chargers laying around.
Geert
What I read in the manual is that each slot also has a “priority button”. When a battery is inserted in that slot and you press the priority button, then that slot will charge immediately to 80%. If you press the priority button twice, it will charge that pack straight to 100%.
Default is that it charges the packs in sequence.
Stuart
Thanks! I asked Bosch USA if there were any user controls, but they never answered that part of my question. Might be different for the international model?
Geert
This was mentioned in the European manual. The priority button is the one which looks like the Youtube play button, and the US model has this button at each port. So it is probably the same.
Stuart
That makes sense. But I asked Bosch USA specifically about user controls regarding 80% charging aspect, and all they told me was about LED indicator lights for pulling the battery off the charger at 80% without having to wait for the top-off charge. So with that, I assumed it was only a “charge this battery first” type of priority button.
JakeJ
Not sure about the European or North America model, but Australia model has some sort of bracket which allows it to be connected to an lboxx.
Geert
Yes, this is also mentioned in the European manual. It is a separate bracket which can be fixed with screws to the bottom of the charger.
Stuart
The multi-voltage battery charger has a wall-mount attachment, but only in Europe and not for the USA model.
https://14cyiuhvcgv.com/bosch-18v-12v-multi-voltage-charger/%3C/a%3E%3C/p%3E
There’s a chance the L-Boxx accessory won’t be available here. I also didn’t see any mention of an L-Boxx accessory on the Bosch USA website.
Indrek
I mentioned both the sequential charging logic as well as the priority button in a comment under your original article about this charger, as well as linking to the EU version manual. Guess you missed it…
Josh
I’m in the middle of building a Bosch drill/charger station. This wouldn’t work with my planned setup, but it’s definitely tempting me to change my plans and just have a 6 port charger plugged in to dump any used batteries into. The 80% charge feature is just gravy.
Plain grainy
Off topic! Home Depot has the Packout compact organizer on sale. I think it’s usually $44.99, on sale for $34.99(22% off). Limit two per order.
Patrick
That’s really impressive for $99.
Cowboy
Question.. If you continually only charge the batteries to 80%, will that have a result that 80% becomes the top charge the battery will take? But eventually indicates that 80% is now the 100% . This is from bad experiences with the older Dewalt batteries and the 12v batteries in other brands.
Nate B
Nope, lithium doesn’t condition itself like that.
If you continually charge the batteries to 80% (and try to avoid flattening them all the way down at the discharge end), the only result is that they last several times longer than batteries that were cycled to extremes.
Assuming the BMS does “top balancing”, it’s probably a good idea to let the pack go to 100% once in a while, because that’s where the voltage differences emerge that allow balancing to take place. But if you’re not using it immediately, it’s best to discharge the pack again, somewhere below 80% — the standard “storage charge” is 40-50%, where minimal degradation occurs.
As far as I know, EGO OPE packs are the only ones that deliberately place themselves in storage charge. It’d be nice to see more battery TLC from major brands.