Earthwalk Sidekick Batteries

[DavidNC]

We are using Earthwalk Sidekick batteries to power some of our laptops (as the laptop batteries are now almost dead). These Sidekick batteries work really well and last for 4 to 6 hours on a full charge. However, we have had problems with them - we had to return them all after a couple of months- and having had them less than 6 months are now having to send 2 back again.

 

Does anyone else have any experience of using these batteries. We would like to order some more, but tat the moment, reliability is an issue.

[synaesthesia]

There's a few things which shout "Avoid me like the plague" about those things.

 

1. You're already having problems and have had to send them all back

2. Their site states 90 day warranties (really?)

3. Their site doesn't actually state any useful specifications about the batteries - i.e. their chemistry/composition. That alone makes me think they shouldn't be anywhere near a school.

4. Overnight charging...

 

I'd strongly recommend just replacing batteries with the OEM equivalents.

[ICTLTD]

We are using Earthwalk Sidekick batteries to power some of our laptops (as the laptop batteries are now almost dead). These Sidekick batteries work really well and last for 4 to 6 hours on a full charge. However, we have had problems with them - we had to return them all after a couple of months- and having had them less than 6 months are now having to send 2 back again.

 

Does anyone else have any experience of using these batteries. We would like to order some more, but tat the moment, reliability is an issue.

 

Hi,

I have never used the sidekicks but I am a bit of a battery geek and have noticed they use NIMH batteries(http://www.earthwalk.com/wp-content/uploads/SideKick-PP_Spec.pdf) which in reality is an older technology with a usual limit of 1.2V per cell. So compared to Li-po (arround 3.7V per Cell) which nearly everything uses now you need a lot more cells to make up the voltage and capacity. That in turn gives you more points of failure, it would only take a few cells to die to make the pack useless due to low voltage.

 

Also NIMH only have a long life if you discharge them and recharge them properly, that means individually (each cell, not each pack in serial). That kind of pack will use many cells in a serial connection and they would soon become out of balance and the odd one would start to become over charged as I can't see it doing individual cell delta peak charging. (that is presumably why they only give 90 day warranty as standard).

That is why Li-po became popular over Ni-MH as it was light weight and due to low amounts of Cells they can use a BMS (Battery management system) that charges individual cells.

As a comparison something like the sidkick will be using around 50 X 1.2V 2000Mah cells to make that battery most laptop (Li-Po) high capacity batteries are 6-9 cells.

Pack charging Ni-MH is tricky and unless proper individual cell charging/discharging is done it will result in cells failing after a few cycles.

Edited November 6, 2012 by ICTLTD